Summary:
This condition is now a normal occurrence during write burst so there is
no need to warn the user about it. Here is a scenario where it happens
under completely normal conditions.
* Initially we have a DB of three levels (L0, L1, and L2) that is stable, i.e., compaction scores are all less than one.
* Now a write burst comes along. At first L0 blows up a bit in size as compaction hasn't had a chance to catch up.
* As a result of the above, `base_bytes_min` also increases since it is based on L0 size as of https://github.com/facebook/rocksdb/issues/4338
* If `base_bytes_min` increased enough (i.e., to be larger than L1), then we are shown the warning that the DB has more levels than necessary.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5742
Differential Revision: D17059221
fbshipit-source-id: e4a31d6eea42089a8d273095f19653991bd91bea
Summary:
VersionSet::ApproximateSize doesn't need to create two separate index iterators and do binary search for each in BlockBasedTable. So BlockBasedTable::ApproximateSize was added that creates the iterator once and uses it to calculate the data size between start and end keys.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5693
Differential Revision: D16774056
Pulled By: elipoz
fbshipit-source-id: 53ce262e1a057788243bf30cd9b8aa6581df1a18
Summary:
Add a command in ldb so that users can print out tombstones in SST files.
In order to test the code, change the interface of LDBCommandRunner::RunCommand() so that it doesn't return from the program, but return the status code.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5615
Test Plan: Add a new unit test
Differential Revision: D16550326
fbshipit-source-id: 88ddfe6984bdcbb3a528abdd115089df09eba52e
Summary:
This is a new API added to db.h to allow for fetching all merge operands associated with a Key. The main motivation for this API is to support use cases where doing a full online merge is not necessary as it is performance sensitive. Example use-cases:
1. Update subset of columns and read subset of columns -
Imagine a SQL Table, a row is encoded as a K/V pair (as it is done in MyRocks). If there are many columns and users only updated one of them, we can use merge operator to reduce write amplification. While users only read one or two columns in the read query, this feature can avoid a full merging of the whole row, and save some CPU.
2. Updating very few attributes in a value which is a JSON-like document -
Updating one attribute can be done efficiently using merge operator, while reading back one attribute can be done more efficiently if we don't need to do a full merge.
----------------------------------------------------------------------------------------------------
API :
Status GetMergeOperands(
const ReadOptions& options, ColumnFamilyHandle* column_family,
const Slice& key, PinnableSlice* merge_operands,
GetMergeOperandsOptions* get_merge_operands_options,
int* number_of_operands)
Example usage :
int size = 100;
int number_of_operands = 0;
std::vector<PinnableSlice> values(size);
GetMergeOperandsOptions merge_operands_info;
db_->GetMergeOperands(ReadOptions(), db_->DefaultColumnFamily(), "k1", values.data(), merge_operands_info, &number_of_operands);
Description :
Returns all the merge operands corresponding to the key. If the number of merge operands in DB is greater than merge_operands_options.expected_max_number_of_operands no merge operands are returned and status is Incomplete. Merge operands returned are in the order of insertion.
merge_operands-> Points to an array of at-least merge_operands_options.expected_max_number_of_operands and the caller is responsible for allocating it. If the status returned is Incomplete then number_of_operands will contain the total number of merge operands found in DB for key.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5604
Test Plan:
Added unit test and perf test in db_bench that can be run using the command:
./db_bench -benchmarks=getmergeoperands --merge_operator=sortlist
Differential Revision: D16657366
Pulled By: vjnadimpalli
fbshipit-source-id: 0faadd752351745224ee12d4ae9ef3cb529951bf
Summary:
In some cases, we don't have to get really accurate number. Something like 10% off is fine, we can create a new option for that use case. In this case, we can calculate size for full files first, and avoid estimation inside SST files if full files got us a huge number. For example, if we already covered 100GB of data, we should be able to skip partial dives into 10 SST files of 30MB.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5609
Differential Revision: D16433481
Pulled By: elipoz
fbshipit-source-id: 5830b31e1c656d0fd3a00d7fd2678ddc8f6e601b
Summary:
RocksDB has historically stored uncompression dictionary objects in the block
cache as opposed to storing just the block contents. This neccesitated
evicting the object upon table close. With the new code, only the raw blocks
are stored in the cache, eliminating the need for eviction.
In addition, the patch makes the following improvements:
1) Compression dictionary blocks are now prefetched/pinned similarly to
index/filter blocks.
2) A copy operation got eliminated when the uncompression dictionary is
retrieved.
3) Errors related to retrieving the uncompression dictionary are propagated as
opposed to silently ignored.
Note: the patch temporarily breaks the compression dictionary evicition stats.
They will be fixed in a separate phase.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5584
Test Plan: make asan_check
Differential Revision: D16344151
Pulled By: ltamasi
fbshipit-source-id: 2962b295f5b19628f9da88a3fcebbce5a5017a7b
Summary:
1. Avoid creating the iterator in order to call BlockBasedTable::ApproximateOffsetOf(). Instead, directly call into it.
2. Optimize BlockBasedTable::ApproximateOffsetOf() keeps the index block iterator in stack.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5613
Differential Revision: D16442660
Pulled By: elipoz
fbshipit-source-id: 9320be3e918c139b10e758cbbb684706d172e516
Summary:
Added log_readahead_size option to control prefetching for Log::Reader.
This is mostly useful for reading a remotely located log, as it can save the number of round-trips when reading it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5592
Differential Revision: D16362989
Pulled By: elipoz
fbshipit-source-id: c5d4d5245a44008cd59879640efff70c091ad3e8
Summary:
RandomAccessFileReader.for_compaction_ doesn't seem to be used anymore. Remove it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5572
Test Plan: USE_CLANG=1 make all check -j
Differential Revision: D16286178
fbshipit-source-id: aa338049761033dfbe5e8b1707bbb0be2df5be7e
Summary:
Since https://github.com/facebook/rocksdb/issues/5468 `LevelIterator` compare lower bound and file smallest key on `NewFileIterator` and cache the result to reduce per key lower bound check. However when iterate across file boundary, it doesn't update the cached result since `Valid()=false` because `Valid()` still reflect the status of the previous file iterator. Fixing it by remove the `Valid()` check from `CheckMayBeOutOfLowerBound()`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5540
Test Plan:
See the new test.
Signed-off-by: Yi Wu <yiwu@pingcap.com>
Differential Revision: D16127653
fbshipit-source-id: a0691e1164658d485c17971aaa97028812f74678
Summary:
This PR associates a unique id with Get and MultiGet. This enables us to track how many blocks a Get/MultiGet request accesses. We can also measure the impact of row cache vs block cache.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5514
Test Plan: make clean && COMPILE_WITH_ASAN=1 make check -j32
Differential Revision: D16032681
Pulled By: HaoyuHuang
fbshipit-source-id: 775b05f4440badd58de6667e3ec9f4fc87a0af4c
Summary:
This PR adds more callers for table readers. These information are only used for block cache analysis so that we can know which caller accesses a block.
1. It renames the BlockCacheLookupCaller to TableReaderCaller as passing the caller from upstream requires changes to table_reader.h and TableReaderCaller is a more appropriate name.
2. It adds more table reader callers in table/table_reader_caller.h, e.g., kCompactionRefill, kExternalSSTIngestion, and kBuildTable.
This PR is long as it requires modification of interfaces in table_reader.h, e.g., NewIterator.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5454
Test Plan: make clean && COMPILE_WITH_ASAN=1 make check -j32.
Differential Revision: D15819451
Pulled By: HaoyuHuang
fbshipit-source-id: b6caa704c8fb96ddd15b9a934b7e7ea87f88092d
Summary:
While the secondary is replaying after the primary, the primary may switch to a new MANIFEST. The secondary is already able to detect and follow the primary to the new MANIFEST. However, the current implementation has a bug, described as follows.
The new MANIFEST's first records have been generated by VersionSet::WriteSnapshot to describe the current state of the column families and the db as of the MANIFEST creation. Since the secondary instance has already finished recovering upon start, there is no need for the secondary to process these records. Actually, if the secondary were to replay these records, the secondary may end up adding the same SST files **again** to each column family, causing consistency checks done by VersionBuilder to fail. Therefore, we record the number of records to skip at the beginning of the new MANIFEST and ignore them.
Test plan (on dev server)
```
$make clean && make -j32 all
$./db_secondary_test
```
All existing unit tests must pass as well.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5472
Differential Revision: D15866771
Pulled By: riversand963
fbshipit-source-id: a1eec4837fb2ad13059398efb0f437e74fd53bed
Summary:
This PR continues the work in https://github.com/facebook/rocksdb/pull/4748 and https://github.com/facebook/rocksdb/pull/4535 by adding a new DBOption `persist_stats_to_disk` which instructs RocksDB to persist stats history to RocksDB itself. When statistics is enabled, and both options `stats_persist_period_sec` and `persist_stats_to_disk` are set, RocksDB will periodically write stats to a built-in column family in the following form: key -> (timestamp in microseconds)#(stats name), value -> stats value. The existing API `GetStatsHistory` will detect the current value of `persist_stats_to_disk` and either read from in-memory data structure or from the hidden column family on disk.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5046
Differential Revision: D15863138
Pulled By: miasantreble
fbshipit-source-id: bb82abdb3f2ca581aa42531734ac799f113e931b
Summary:
This PR integrates the block cache tracer class into db_impl.cc.
db_impl.cc contains a member variable of AtomicBlockCacheTraceWriter class and passes its reference to the block_based_table_reader.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5433
Differential Revision: D15728016
Pulled By: HaoyuHuang
fbshipit-source-id: 23d5659e8c82d556833dcc1a5558aac8c1f7db71
Summary:
BlockCacheLookupContext only contains the caller for now.
We will trace block accesses at five places:
1. BlockBasedTable::GetFilter.
2. BlockBasedTable::GetUncompressedDict.
3. BlockBasedTable::MaybeReadAndLoadToCache. (To trace access on data, index, and range deletion block.)
4. BlockBasedTable::Get. (To trace the referenced key and whether the referenced key exists in a fetched data block.)
5. BlockBasedTable::MultiGet. (To trace the referenced key and whether the referenced key exists in a fetched data block.)
We create the context at:
1. BlockBasedTable::Get. (kUserGet)
2. BlockBasedTable::MultiGet. (kUserMGet)
3. BlockBasedTable::NewIterator. (either kUserIterator, kCompaction, or external SST ingestion calls this function.)
4. BlockBasedTable::Open. (kPrefetch)
5. Index/Filter::CacheDependencies. (kPrefetch)
6. BlockBasedTable::ApproximateOffsetOf. (kCompaction or kUserApproximateSize).
I loaded 1 million key-value pairs into the database and ran the readrandom benchmark with a single thread. I gave the block cache 10 GB to make sure all reads hit the block cache after warmup. The throughput is comparable.
Throughput of this PR: 231334 ops/s.
Throughput of the master branch: 238428 ops/s.
Experiment setup:
RocksDB: version 6.2
Date: Mon Jun 10 10:42:51 2019
CPU: 24 * Intel Core Processor (Skylake)
CPUCache: 16384 KB
Keys: 20 bytes each
Values: 100 bytes each (100 bytes after compression)
Entries: 1000000
Prefix: 20 bytes
Keys per prefix: 0
RawSize: 114.4 MB (estimated)
FileSize: 114.4 MB (estimated)
Write rate: 0 bytes/second
Read rate: 0 ops/second
Compression: NoCompression
Compression sampling rate: 0
Memtablerep: skip_list
Perf Level: 1
Load command: ./db_bench --benchmarks="fillseq" --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 --statistics --cache_index_and_filter_blocks --cache_size=10737418240 --disable_auto_compactions=1 --disable_wal=1 --compression_type=none --min_level_to_compress=-1 --compression_ratio=1 --num=1000000
Run command: ./db_bench --benchmarks="readrandom,stats" --use_existing_db --threads=1 --duration=120 --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 --statistics --cache_index_and_filter_blocks --cache_size=10737418240 --disable_auto_compactions=1 --disable_wal=1 --compression_type=none --min_level_to_compress=-1 --compression_ratio=1 --num=1000000 --duration=120
TODOs:
1. Create a caller for external SST file ingestion and differentiate the callers for iterator.
2. Integrate tracer to trace block cache accesses.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5421
Differential Revision: D15704258
Pulled By: HaoyuHuang
fbshipit-source-id: 4aa8a55f8cb1576ffb367bfa3186a91d8f06d93a
Summary:
When using `PRIu64` type of printf specifier, current code base does the following:
```
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
```
However, this can be simplified to
```
#include <cinttypes>
```
as long as flag `-std=c++11` is used.
This should solve issues like https://github.com/facebook/rocksdb/issues/5159
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5402
Differential Revision: D15701195
Pulled By: miasantreble
fbshipit-source-id: 6dac0a05f52aadb55e9728038599d3d2e4b59d03
Summary:
It's useful to be able to (optionally) associate key-value pairs with user-provided timestamps. This PR is an early effort towards this goal and continues the work of facebook#4942. A suite of new unit tests exist in DBBasicTestWithTimestampWithParam. Support for timestamp requires the user to provide timestamp as a slice in `ReadOptions` and `WriteOptions`. All timestamps of the same database must share the same length, format, etc. The format of the timestamp is the same throughout the same database, and the user is responsible for providing a comparator function (Comparator) to order the <key, timestamp> tuples. Once created, the format and length of the timestamp cannot change (at least for now).
Test plan (on devserver):
```
$COMPILE_WITH_ASAN=1 make -j32 all
$./db_basic_test --gtest_filter=Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/*
$make check
```
All tests must pass.
We also run the following db_bench tests to verify whether there is regression on Get/Put while timestamp is not enabled.
```
$TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillseq,readrandom -num=1000000
$TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillrandom -num=1000000
```
Repeat for 6 times for both versions.
Results are as follows:
```
| | readrandom | fillrandom |
| master | 16.77 MB/s | 47.05 MB/s |
| PR5079 | 16.44 MB/s | 47.03 MB/s |
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5079
Differential Revision: D15132946
Pulled By: riversand963
fbshipit-source-id: 833a0d657eac21182f0f206c910a6438154c742c
Summary:
With this commit, RocksDB secondary instance respects atomic groups in version edits.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5411
Differential Revision: D15617512
Pulled By: HaoyuHuang
fbshipit-source-id: 913f4ede391d772dcaf5649e3cd2099fa292d120
Summary:
There are too many types of files under util/. Some test related files don't belong to there or just are just loosely related. Mo
ve them to a new directory test_util/, so that util/ is cleaner.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5377
Differential Revision: D15551366
Pulled By: siying
fbshipit-source-id: 0f5c8653832354ef8caa31749c0143815d719e2c
Summary:
util/ means for lower level libraries, so it's a good idea to move the files which requires knowledge to DB out. Create a file/ and move some files there.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5375
Differential Revision: D15550935
Pulled By: siying
fbshipit-source-id: 61a9715dcde5386eebfb43e93f847bba1ae0d3f2
Summary:
In version_set.cc, there is a function GetCurrentManifestPath. The goal of this task is to refactor ListColumnFamilies function so that ListColumnFamilies calls GetCurrentManifestPath to search for MANIFEST.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5331
Differential Revision: D15444524
Pulled By: HaoyuHuang
fbshipit-source-id: 1dcbd030bc0f2e835695741f450bba150f2f2903
Summary:
Previously if iterator upper/lower bound presents, `DBIter` will check the bound for every key. This patch turns the check into per-file or per-data block check when applicable, by checking against either file largest/smallest key or block index key.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5111
Differential Revision: D15330061
Pulled By: siying
fbshipit-source-id: 8a653fe3cd50d94d81eb2d13b087326c58ee2024
Summary:
This PR has two fixes for crash test failures -
1. Fix a bug in TestMultiGet() in db_stress that was passing list of key to MultiGet() in the wrong order, thus ensuring that actual values don't match expected values
2. Remove an incorrect assertion in FilePickerMultiGet::GetNextFileInLevelWithKeys() that checks that files in a level are in sorted order. This is not true with MultiGet(), especially if there are duplicate keys and we may have to go back one file for the next key. Furthermore, this assertion makes more sense when a new version is created, rather than at lookup time
Test -
asan_crash and ubsan_crash tests
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5301
Differential Revision: D15337383
Pulled By: anand1976
fbshipit-source-id: 35092cb15bbc1700e5e823cbe07bfa62f1e9e6c6
Summary:
When reseek happens in merging iterator, reseeking a child iterator can be avoided if:
(1) the iterator represents imutable data
(2) reseek() to a larger key than the current key
(3) the current key of the child iterator is larger than the seek key
because it is guaranteed that the result will fall into the same position.
This optimization will be useful for use cases where users keep seeking to keys nearby in ascending order.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5286
Differential Revision: D15283635
Pulled By: siying
fbshipit-source-id: 35f79ffd5ce3609146faa8cd55f2bfd733502f83
Summary:
This PR fixes a couple of bugs in FilePickerMultiGet that were causing db_stress test failures. The failures were caused by -
1. Improper handling of a key that matches the user key portion of an L0 file's largest key. In this case, the curr_index_in_curr_level file index in L0 for that key was getting incremented, but batch_iter_ was not advanced. By design, all keys in a batch are supposed to be checked against an L0 file before advancing to the next L0 file. Not advancing to the next key in the batch was causing a double increment of curr_index_in_curr_level due to the same key being processed again
2. Improper handling of a key that matches the user key portion of the largest key in the last file of L1 and higher. This was resulting in a premature end to the processing of the batch for that level when the next key in the batch is a duplicate. Typically, the keys in MultiGet will not be duplicates, but its good to handle that case correctly
Test -
asan_crash
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5292
Differential Revision: D15282530
Pulled By: anand1976
fbshipit-source-id: d1a6a86e0af273169c3632db22a44d79c66a581f
Summary:
This PR fixes three memory issues found by ASAN
* in db_stress, the key vector for MultiGet is created using `emplace_back` which could potentially invalidates references to the underlying storage (vector<string>) due to auto resizing. Fix by calling reserve in advance.
* Similar issue in construction of GetContext autovector in version_set.cc
* In multiget_context.h use T[] specialization for unique_ptr that holds a char array
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5279
Differential Revision: D15202893
Pulled By: miasantreble
fbshipit-source-id: 14cc2cda0ed64d29f2a1e264a6bfdaa4294ee75d
Summary:
Right now, when Seek() is called again, RocksDB always does a binary search against the files and index blocks, even if they end up with the same file/block. Improve it as following:
1. in LevelIterator, reseek first try to check the boundary of the current file. If it falls into the same file, skip the binary search to find the file
2. in block based table iterator, reseek skip to reseek the iterator block if the seek key is larger than the current key and lower than the index key (boundary of the current block and the next block).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5256
Differential Revision: D15105072
Pulled By: siying
fbshipit-source-id: 39634bdb4a881082451fa39cecd7ecf12160bf80
Summary:
In some cases, we want to known the smallest and largest sequence numbers of sstable files, to help us get more details.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5231
Differential Revision: D15038087
Pulled By: siying
fbshipit-source-id: c473c1ca07b53efe2f1884fa1ecdc8686f455ed8
Summary:
We found an issue in Periodic Compactions (introduced in #5166) where files were not being picked up for compactions as all the SST files created with older versions of RocksDB have `file_creation_time` as 0. (Note that `file_creation_time` is a new table property introduced in #5166).
To address this, Periodic compactions now fall back to looking at the `creation_time` table property or the file's modification time (as given by the Env) when `file_creation_time` table property is found to be 0.
Here how the file's modification time (and, in turn, the file age) is computed now:
1. Use `file_creation_time` table property if it is > 0.
1. If not, then use `creation_time` table property if it is > 0.
1. If not, then use file's mtime stat metadata given by the underlying Env.
Don't consider the file at all for compaction if the modification time cannot be correctly determined based on the above conditions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5184
Differential Revision: D14907795
Pulled By: sagar0
fbshipit-source-id: 4bb2f3631f9a3e04470c674a1d13544584e1e56c
Summary:
In long scans, virtual function calls of Next(), Valid(), key() and value() are not trivial. By introducing NextAndGetResult(), Some of the Next(), Valid() and key() calls are consolidated into one virtual function call to reduce CPU.
Also did some inline tricks and add some "final" randomly in some functions. Even without the "final" annotation, most Next() calls are inlined with -O3, but sometimes with a final it is inlined by O2 too. It doesn't hurt to add those final annotations.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5197
Differential Revision: D14945977
Pulled By: siying
fbshipit-source-id: 7003969f9a5f1d5717f0bda503b91d19ba75ed88
Summary:
`GetOverlappingInputsRangeBinarySearch` firstly use binary search
to find a index in the given range `[begin, end]`. But after find
the index, then use linear search to find the `start_index` and
`end_index`. So the search process degraded to linear time.
Here optmize the search process with below changes:
- use `std::lower_bound` and `std::upper_bound` to get
`lg(n)` search complexity.
- use uniformed lambda for search process.
- simplify process for `within_interval` true or false.
- remove function `ExtendFileRangeWithinInterval`
and `ExtendFileRangeOverlappingInterval`.
Signed-off-by: JiYou <jiyou09@gmail.com>
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4987
Differential Revision: D14984192
Pulled By: riversand963
fbshipit-source-id: fae4b8e59a21b7e350718d60cdc94dd55ac81e89
Summary:
This PR introduces a new MultiGet() API, with the underlying implementation grouping keys based on SST file and batching lookups in a file. The reason for the new API is twofold - the definition allows callers to allocate storage for status and values on stack instead of std::vector, as well as return values as PinnableSlices in order to avoid copying, and it keeps the original MultiGet() implementation intact while we experiment with batching.
Batching is useful when there is some spatial locality to the keys being queries, as well as larger batch sizes. The main benefits are due to -
1. Fewer function calls, especially to BlockBasedTableReader::MultiGet() and FullFilterBlockReader::KeysMayMatch()
2. Bloom filter cachelines can be prefetched, hiding the cache miss latency
The next step is to optimize the binary searches in the level_storage_info, index blocks and data blocks, since we could reduce the number of key comparisons if the keys are relatively close to each other. The batching optimizations also need to be extended to other formats, such as PlainTable and filter formats. This also needs to be added to db_stress.
Benchmark results from db_bench for various batch size/locality of reference combinations are given below. Locality was simulated by offsetting the keys in a batch by a stride length. Each SST file is about 8.6MB uncompressed and key/value size is 16/100 uncompressed. To focus on the cpu benefit of batching, the runs were single threaded and bound to the same cpu to eliminate interference from other system events. The results show a 10-25% improvement in micros/op from smaller to larger batch sizes (4 - 32).
Batch Sizes
1 | 2 | 4 | 8 | 16 | 32
Random pattern (Stride length 0)
4.158 | 4.109 | 4.026 | 4.05 | 4.1 | 4.074 - Get
4.438 | 4.302 | 4.165 | 4.122 | 4.096 | 4.075 - MultiGet (no batching)
4.461 | 4.256 | 4.277 | 4.11 | 4.182 | 4.14 - MultiGet (w/ batching)
Good locality (Stride length 16)
4.048 | 3.659 | 3.248 | 2.99 | 2.84 | 2.753
4.429 | 3.728 | 3.406 | 3.053 | 2.911 | 2.781
4.452 | 3.45 | 2.833 | 2.451 | 2.233 | 2.135
Good locality (Stride length 256)
4.066 | 3.786 | 3.581 | 3.447 | 3.415 | 3.232
4.406 | 4.005 | 3.644 | 3.49 | 3.381 | 3.268
4.393 | 3.649 | 3.186 | 2.882 | 2.676 | 2.62
Medium locality (Stride length 4096)
4.012 | 3.922 | 3.768 | 3.61 | 3.582 | 3.555
4.364 | 4.057 | 3.791 | 3.65 | 3.57 | 3.465
4.479 | 3.758 | 3.316 | 3.077 | 2.959 | 2.891
dbbench command used (on a DB with 4 levels, 12 million keys)-
TEST_TMPDIR=/dev/shm numactl -C 10 ./db_bench.tmp -use_existing_db=true -benchmarks="readseq,multireadrandom" -write_buffer_size=4194304 -target_file_size_base=4194304 -max_bytes_for_level_base=16777216 -num=12000000 -reads=12000000 -duration=90 -threads=1 -compression_type=none -cache_size=4194304000 -batch_size=32 -disable_auto_compactions=true -bloom_bits=10 -cache_index_and_filter_blocks=true -pin_l0_filter_and_index_blocks_in_cache=true -multiread_batched=true -multiread_stride=4
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5011
Differential Revision: D14348703
Pulled By: anand1976
fbshipit-source-id: 774406dab3776d979c809522a67bedac6c17f84b
Summary:
Introducing Periodic Compactions.
This feature allows all the files in a CF to be periodically compacted. It could help in catching any corruptions that could creep into the DB proactively as every file is constantly getting re-compacted. And also, of course, it helps to cleanup data older than certain threshold.
- Introduced a new option `periodic_compaction_time` to control how long a file can live without being compacted in a CF.
- This works across all levels.
- The files are put in the same level after going through the compaction. (Related files in the same level are picked up as `ExpandInputstoCleanCut` is used).
- Compaction filters, if any, are invoked as usual.
- A new table property, `file_creation_time`, is introduced to implement this feature. This property is set to the time at which the SST file was created (and that time is given by the underlying Env/OS).
This feature can be enabled on its own, or in conjunction with `ttl`. It is possible to set a different time threshold for the bottom level when used in conjunction with ttl. Since `ttl` works only on 0 to last but one levels, you could set `ttl` to, say, 1 day, and `periodic_compaction_time` to, say, 7 days. Since `ttl < periodic_compaction_time` all files in last but one levels keep getting picked up based on ttl, and almost never based on periodic_compaction_time. The files in the bottom level get picked up for compaction based on `periodic_compaction_time`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5166
Differential Revision: D14884441
Pulled By: sagar0
fbshipit-source-id: 408426cbacb409c06386a98632dcf90bfa1bda47
Summary:
Annotate all of the logging functions to inform the compiler that these
use printf-style formatting arguments. This allows the compiler to emit
warnings if the format arguments are incorrect.
This also fixes many problems reported now that format string checking
is enabled. Many of these are simply mix-ups in the argument type (e.g,
int vs uint64_t), but in several cases the wrong number of arguments
were being passed in which can cause the code to crash.
The primary motivation for this was to fix the log message in
`DBImpl::SwitchMemtable()` which caused a segfault due to an extra %s
format parameter with no argument supplied.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5089
Differential Revision: D14574795
Pulled By: simpkins
fbshipit-source-id: 0921b03f0743652bf4ae21e414ff54b3bb65422a
Summary:
Currently `perf_context.user_key_comparison_count` is bump only in `InternalKeyComparator`. For places user comparator is used directly the counter is not bump. Fixing the majority of it.
Index iterator and filter code also use user comparator directly and don't bump the counter. It is not fixed in this patch.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5098
Differential Revision: D14603753
Pulled By: siying
fbshipit-source-id: 1cd41035644ca9e49b97a51030a5d1e15f5f3cae
Summary:
This PR allows RocksDB to run in single-primary, multi-secondary process mode.
The writer is a regular RocksDB (e.g. an `DBImpl`) instance playing the role of a primary.
Multiple `DBImplSecondary` processes (secondaries) share the same set of SST files, MANIFEST, WAL files with the primary. Secondaries tail the MANIFEST of the primary and apply updates to their own in-memory state of the file system, e.g. `VersionStorageInfo`.
This PR has several components:
1. (Originally in #4745). Add a `PathNotFound` subcode to `IOError` to denote the failure when a secondary tries to open a file which has been deleted by the primary.
2. (Similar to #4602). Add `FragmentBufferedReader` to handle partially-read, trailing record at the end of a log from where future read can continue.
3. (Originally in #4710 and #4820). Add implementation of the secondary, i.e. `DBImplSecondary`.
3.1 Tail the primary's MANIFEST during recovery.
3.2 Tail the primary's MANIFEST during normal processing by calling `ReadAndApply`.
3.3 Tailing WAL will be in a future PR.
4. Add an example in 'examples/multi_processes_example.cc' to demonstrate the usage of secondary RocksDB instance in a multi-process setting. Instructions to run the example can be found at the beginning of the source code.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4899
Differential Revision: D14510945
Pulled By: riversand963
fbshipit-source-id: 4ac1c5693e6012ad23f7b4b42d3c374fecbe8886
Summary:
We introduced ttl option in CompactionOptionsFIFO when ttl-based file
deletion (compaction) was supported only as part of FIFO Compaction. But
with the extension of ttl semantics even to Level compaction,
CompactionOptionsFIFO.ttl can now be deprecated. Instead we will start
using ColumnFamilyOptions.ttl for FIFO compaction as well.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4965
Differential Revision: D14072960
Pulled By: sagar0
fbshipit-source-id: c98cc2ae695a28136295787cd88d36a220fc219e
Summary:
Make file ingestion atomic.
as title.
Ingesting external SST files into multiple column families should be atomic. If
a crash occurs and db reopens, either all column families have successfully
ingested the files before the crash, or non of the ingestions have any effect
on the state of the db.
Also add unit tests for atomic ingestion.
Note that the unit test here does not cover the case of incomplete atomic group
in the MANIFEST, which is covered in VersionSetTest already.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4895
Differential Revision: D13718245
Pulled By: riversand963
fbshipit-source-id: 7df97cc483af73ad44dd6993008f99b083852198
Summary:
Measure CPU time consumed for a compaction and report it in the stats report
Enable NowCPUNanos() to work for MacOS
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4889
Differential Revision: D13701276
Pulled By: zinoale
fbshipit-source-id: 5024e5bbccd4dd10fd90d947870237f436445055
Summary:
Right now, CompactionPri = kMinOverlappingRatio provides best write amplification, but it doesn't
prioritize files with more tombstones. We combine the two good features: make kMinOverlappingRatio
to boost files with lots of tombstones too.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4907
Differential Revision: D13788774
Pulled By: siying
fbshipit-source-id: 1991cbb495fb76c8b529de69896e38d81ed9d9b3
Summary:
https://github.com/facebook/rocksdb/pull/3340 introduces preloading when max_open_files != -1.
It doesn't preload index and filter in non-initial file loading case. This is a little bit too
complicated to understand. We observed in one MyRocks use case where the filter is expected to be
preloaded but is not. To simplify the use case, we simply always prefetch the index and filter.
They anyway is expected to be loaded in the file verification phase anyway.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4852
Differential Revision: D13595402
Pulled By: siying
fbshipit-source-id: d4d8624eb3e849e20aeb990df2100502d85aff31
Summary:
Previously for point lookup we decided which file to look into based on user key overlap only. We also did not truncate range tombstones in the point lookup code path. These two ideas did not interact well in cases like this:
- L1 has range tombstone [a, c)#1 and point key b#2. The data is split between file1 with range [a#1,1, b#72057594037927935,15], and file2 with range [b#2, c#1].
- L1's file2 gets compacted to L2.
- User issues `Get()` for b#3.
- L1's file1 is opened and the range tombstone [a, c)#1 is found for b, while no point-key for b is found in L1.
- `Get()` assumes that the range tombstone must cover all data in that range in lower levels, so short circuits and returns `NotFound`.
The solution to this problem is to not look into files that only overlap with the point lookup at a range tombstone sentinel endpoint. In the above example, this would mean not opening L1's file1 or its tombstones during the `Get()`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4829
Differential Revision: D13561355
Pulled By: ajkr
fbshipit-source-id: a13c21c816870a2f5d32a48af6dbd719a7d9d19f
Summary:
Choose to preload some files if options.max_open_files != -1. This can slightly narrow the gap of performance between options.max_open_files is -1 and a large number. To avoid a significant regression to DB reopen speed if options.max_open_files != -1. Limit the files to preload in DB open time to 16.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3340
Differential Revision: D6686945
Pulled By: siying
fbshipit-source-id: 8ec11bbdb46e3d0cdee7b6ad5897a09c5a07869f
Summary:
Now that v2 is fully functional, the v1 aggregator is removed.
The v2 aggregator has been renamed.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4778
Differential Revision: D13495930
Pulled By: abhimadan
fbshipit-source-id: 9d69500a60a283e79b6c4fa938fc68a8aa4d40d6
Summary:
RangeDelAggregatorV2 now supports ShouldDelete calls on
snapshot stripes and creation of range tombstone compaction iterators.
RangeDelAggregator is no longer used on any non-test code path, and will
be removed in a future commit.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4758
Differential Revision: D13439254
Pulled By: abhimadan
fbshipit-source-id: fe105bcf8e3d4a2df37a622d5510843cd71b0401
Summary:
If one column family is dropped, we should simply skip it and continue to flush
other active ones.
Currently we use Status::ShutdownInProgress to notify caller of column families
being dropped. In the future, we should consider using a different Status code.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4708
Differential Revision: D13378954
Pulled By: riversand963
fbshipit-source-id: 42f248cdf2d32d4c0f677cd39012694b8f1328ca
Summary:
…ons (#4676)"
This reverts commit b32d087dbb.
`MemoryAllocator` needs to be with `Cache`, since cache entry can
outlive DB and block based table. The cache needs to hold reference to
memory allocator when deleting cache entry.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4697
Differential Revision: D13133490
Pulled By: yiwu-arbug
fbshipit-source-id: 8ef7e8a51263bfd929f892fd062665ff4ce9ce5a
Summary:
The old RangeDelAggregator did expensive pre-processing work
to create a collapsed, binary-searchable representation of range
tombstones. With FragmentedRangeTombstoneIterator, much of this work is
now unnecessary. RangeDelAggregatorV2 takes advantage of this by seeking
in each iterator to find a covering tombstone in ShouldDelete, while
doing minimal work in AddTombstones. The old RangeDelAggregator is still
used during flush/compaction for now, though RangeDelAggregatorV2 will
support those uses in a future PR.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4649
Differential Revision: D13146964
Pulled By: abhimadan
fbshipit-source-id: be29a4c020fc440500c137216fcc1cf529571eb3
Summary:
Since a range tombstone seen at one level will cover all keys
in the range at lower levels, there was a short-circuiting check in Get
that reported a key was not found at most one file after the range
tombstone was discovered. However, this was incorrect for merge
operands, since a deletion might only cover some merge operands,
which implies that the key should be found. This PR fixes this logic in
the Version portion of Get, and removes the logic from the MemTable
portion of Get, since the perforamnce benefit provided there is minimal.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4698
Differential Revision: D13142484
Pulled By: abhimadan
fbshipit-source-id: cbd74537c806032f2bfa564724d01a80df7c8f10
Summary:
This is a quick fix for the uninitialized bugs in `LiveFileMetaData` and `SstFileMetaData` that were uncovered in #4686.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4693
Differential Revision: D13113189
Pulled By: ajkr
fbshipit-source-id: 18e798d031d2a59d0b55fc010c135e0126f4042d
Summary:
Per offline discussion with siying, `MemoryAllocator` and `Cache` should be decouple. The idea is that memory allocator handles memory allocation, while cache handle cache policy.
It is normal that external cache libraries pack couple the two components for better optimization. If we want to integrate with such library in the future, we can make a wrapper of the library implementing both `Cache` and `MemoryAllocator` interface.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4676
Differential Revision: D13047662
Pulled By: yiwu-arbug
fbshipit-source-id: cd42e246d80ab600b4de47d073f7d2db308ce6dd
Summary:
he ratio of num_deletions to num_entries of a level can be useful to determine if a manual compaction needs to be triggered on a level.
Also refer #3980
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4623
Differential Revision: D13045744
Pulled By: sagar0
fbshipit-source-id: 71f3c8e363a8ffd194ec3bb0ed0b69612231f0b3
Summary:
this PR adds two more per-level perf context counters to track
* number of keys returned in Get call, break down by levels
* total processing time at each level during Get call
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4617
Differential Revision: D12898024
Pulled By: miasantreble
fbshipit-source-id: 6b84ef1c8097c0d9e97bee1a774958f56ab4a6c4
Summary:
Ran the following commands to recursively change all the files under RocksDB:
```
find . -type f -name "*.cc" -exec sed -i 's/ unique_ptr/ std::unique_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/<unique_ptr/<std::unique_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/ shared_ptr/ std::shared_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/<shared_ptr/<std::shared_ptr/g' {} +
```
Running `make format` updated some formatting on the files touched.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4638
Differential Revision: D12934992
Pulled By: sagar0
fbshipit-source-id: 45a15d23c230cdd64c08f9c0243e5183934338a8
Summary:
Add unit tests to demonstrate that `VersionSet::Recover` is able to detect and handle cases in which the MANIFEST has valid atomic group, incomplete trailing atomic group, atomic group mixed with normal version edits and atomic group with incorrect size.
With this capability, RocksDB identifies non-valid groups of version edits and do not apply them, thus guaranteeing that the db is restored to a state consistent with the most recent successful atomic flush before applying WAL.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4433
Differential Revision: D10079202
Pulled By: riversand963
fbshipit-source-id: a0e0b8bf4da1cf68e044d397588c121b66c68876
Summary:
Since the number of range deletions are reported in
TableProperties, it is confusing to not report the number of merge
operands and point deletions as top-level properties; they are
accessible through the public API, but since they are not the "main"
properties, they do not appear in aggregated table properties, or the
string representation of table properties.
This change promotes those two property keys to
`rocksdb/table_properties.h`, adds corresponding uint64 members for
them, deprecates the old access methods `GetDeletedKeys()` and
`GetMergeOperands()` (though they are still usable for now), and removes
`InternalKeyPropertiesCollector`. The property key strings are the same
as before this change, so this should be able to read DBs written from older
versions (though I haven't tested this yet).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4594
Differential Revision: D12826893
Pulled By: abhimadan
fbshipit-source-id: 9e4e4fbdc5b0da161c89582566d184101ba8eb68
Summary:
This allows tombstone fragmenting to only be performed when the table is opened, and cached for subsequent accesses.
On the same DB used in #4449, running `readrandom` results in the following:
```
readrandom : 0.983 micros/op 1017076 ops/sec; 78.3 MB/s (63103 of 100000 found)
```
Now that Get performance in the presence of range tombstones is reasonable, I also compared the performance between a DB with range tombstones, "expanded" range tombstones (several point tombstones that cover the same keys the equivalent range tombstone would cover, a common workaround for DeleteRange), and no range tombstones. The created DBs had 5 million keys each, and DeleteRange was called at regular intervals (depending on the total number of range tombstones being written) after 4.5 million Puts. The table below summarizes the results of a `readwhilewriting` benchmark (in order to provide somewhat more realistic results):
```
Tombstones? | avg micros/op | stddev micros/op | avg ops/s | stddev ops/s
----------------- | ------------- | ---------------- | ------------ | ------------
None | 0.6186 | 0.04637 | 1,625,252.90 | 124,679.41
500 Expanded | 0.6019 | 0.03628 | 1,666,670.40 | 101,142.65
500 Unexpanded | 0.6435 | 0.03994 | 1,559,979.40 | 104,090.52
1k Expanded | 0.6034 | 0.04349 | 1,665,128.10 | 125,144.57
1k Unexpanded | 0.6261 | 0.03093 | 1,600,457.50 | 79,024.94
5k Expanded | 0.6163 | 0.05926 | 1,636,668.80 | 154,888.85
5k Unexpanded | 0.6402 | 0.04002 | 1,567,804.70 | 100,965.55
10k Expanded | 0.6036 | 0.05105 | 1,667,237.70 | 142,830.36
10k Unexpanded | 0.6128 | 0.02598 | 1,634,633.40 | 72,161.82
25k Expanded | 0.6198 | 0.04542 | 1,620,980.50 | 116,662.93
25k Unexpanded | 0.5478 | 0.0362 | 1,833,059.10 | 121,233.81
50k Expanded | 0.5104 | 0.04347 | 1,973,107.90 | 184,073.49
50k Unexpanded | 0.4528 | 0.03387 | 2,219,034.50 | 170,984.32
```
After a large enough quantity of range tombstones are written, range tombstone Gets can become faster than reading from an equivalent DB with several point tombstones.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4493
Differential Revision: D10842844
Pulled By: abhimadan
fbshipit-source-id: a7d44534f8120e6aabb65779d26c6b9df954c509
Summary:
Previously, range tombstones were accumulated from every level, which
was necessary if a range tombstone in a higher level covered a key in a lower
level. However, RangeDelAggregator::AddTombstones's complexity is based on
the number of tombstones that are currently stored in it, which is wasteful in
the Get case, where we only need to know the highest sequence number of range
tombstones that cover the key from higher levels, and compute the highest covering
sequence number at the current level. This change introduces this optimization, and
removes the use of RangeDelAggregator from the Get path.
In the benchmark results, the following command was used to initialize the database:
```
./db_bench -db=/dev/shm/5k-rts -use_existing_db=false -benchmarks=filluniquerandom -write_buffer_size=1048576 -compression_type=lz4 -target_file_size_base=1048576 -max_bytes_for_level_base=4194304 -value_size=112 -key_size=16 -block_size=4096 -level_compaction_dynamic_level_bytes=true -num=5000000 -max_background_jobs=12 -benchmark_write_rate_limit=20971520 -range_tombstone_width=100 -writes_per_range_tombstone=100 -max_num_range_tombstones=50000 -bloom_bits=8
```
...and the following command was used to measure read throughput:
```
./db_bench -db=/dev/shm/5k-rts/ -use_existing_db=true -benchmarks=readrandom -disable_auto_compactions=true -num=5000000 -reads=100000 -threads=32
```
The filluniquerandom command was only run once, and the resulting database was used
to measure read performance before and after the PR. Both binaries were compiled with
`DEBUG_LEVEL=0`.
Readrandom results before PR:
```
readrandom : 4.544 micros/op 220090 ops/sec; 16.9 MB/s (63103 of 100000 found)
```
Readrandom results after PR:
```
readrandom : 11.147 micros/op 89707 ops/sec; 6.9 MB/s (63103 of 100000 found)
```
So it's actually slower right now, but this PR paves the way for future optimizations (see #4493).
----
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4449
Differential Revision: D10370575
Pulled By: abhimadan
fbshipit-source-id: 9a2e152be1ef36969055c0e9eb4beb0d96c11f4d
Summary:
There was a bug that the user comparator would receive the internal key instead of the user key. The bug was due to RangeMightExistAfterSortedRun expecting user key but receiving internal key when called in GenerateBottommostFiles. The patch augment an existing unit test to reproduce the bug and fixes it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4575
Differential Revision: D10500434
Pulled By: maysamyabandeh
fbshipit-source-id: 858346d2fd102cce9e20516d77338c112bdfe366
Summary:
Level compaction usually performs poorly when the writes so heavy that the level targets can't be guaranteed. With this improvement, we improve level_compaction_dynamic_level_bytes = true so that in the write heavy cases, the level multiplier can be slightly adjusted based on the size of L0.
We keep the behavior the same if number of L0 files is under 2X compaction trigger and the total size is less than options.max_bytes_for_level_base, so that unless write is so heavy that compaction cannot keep up, the behavior doesn't change.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4338
Differential Revision: D9636782
Pulled By: siying
fbshipit-source-id: e27fc17a7c29c84b00064cc17536a01dacef7595
Summary:
Current `log::Reader` does not perform retry after encountering `EOF`. In the future, we need the log reader to be able to retry tailing the log even after `EOF`.
Current implementation is simple. It does not provide more advanced retry policies. Will address this in the future.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4394
Differential Revision: D9926508
Pulled By: riversand963
fbshipit-source-id: d86d145792a41bd64a72f642a2a08c7b7b5201e1
Summary:
When a CompactRange() call for a level is truncated before the end key
is reached, because it exceeds max_compaction_bytes, we need to properly
set the compaction_end parameter to indicate the stop key. The next
CompactRange will use that as the begin key. We set it to the smallest
key of the next file in the level after expanding inputs to get a clean
cut.
Previously, we were setting it before expanding inputs. So we could end
up recompacting some files. In a pathological case, where a single key
has many entries spanning all the files in the level (possibly due to
merge operands without a partial merge operator, thus resulting in
compaction output identical to the input), this would result in
an endless loop over the same set of files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4496
Differential Revision: D10395026
Pulled By: anand1976
fbshipit-source-id: f0c2f89fee29b4b3be53b6467b53abba8e9146a9
Summary:
Leverage existing `FlushJob` to implement atomic flush of multiple column families.
This PR depends on other PRs and is a subset of #3752 . This PR itself is not sufficient in fulfilling atomic flush.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4262
Differential Revision: D9283109
Pulled By: riversand963
fbshipit-source-id: 65401f913e4160b0a61c0be6cd02adc15dad28ed
Summary:
We would like to collect file-system-level statistics including file name, offset, length, return code, latency, etc., which requires to add callbacks to intercept file IO function calls when RocksDB is running.
To collect file-system-level statistics, users can inherit the class `EventListener`, as in `TestFileOperationListener `. Note that `TestFileOperationListener::ShouldBeNotifiedOnFileIO()` returns true.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3933
Differential Revision: D10219571
Pulled By: riversand963
fbshipit-source-id: 7acc577a2d31097766a27adb6f78eaf8b1e8ff15
Summary:
To more accurately truncate range tombstones at SST boundaries,
we now represent them in RangeDelAggregator using InternalKeys, which
are end-key-exclusive as they were before this change.
During compaction, "atomic compaction unit boundaries" (the range of
keys contained in neighbouring and overlaping SSTs) are propagated down
to RangeDelAggregator to truncate range tombstones at those boundariies
instead. See https://github.com/facebook/rocksdb/pull/4432#discussion_r221072219 and https://github.com/facebook/rocksdb/pull/4432#discussion_r221138683
for motivating examples.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4432
Differential Revision: D10263952
Pulled By: abhimadan
fbshipit-source-id: 2fe85ff8a02b3a6a2de2edfe708012797a7bd579
Summary:
This fix is for `level == 0` in `GetOverlappingInputs()`:
- In `GetOverlappingInputs()`, if `level == 0`, it has potential
risk of overflow if `i == 0`.
- Optmize process when `expand = true`, the expected complexity
can be reduced to O(n).
Signed-off-by: JiYou <jiyou09@gmail.com>
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4385
Differential Revision: D10181001
Pulled By: riversand963
fbshipit-source-id: 46eef8a1d1605c9329c164e6471cd5c5b6de16b5
Summary:
`FindFile()` and `FindFileInRange()` actually works as the same
of `std::lower_bound()`. Use `std::lower_bound()` to reduce the
repeated code.
- change `FindFile()` and `FindFileInRange()` to use `std::lower_bound()`
Signed-off-by: JiYou <jiyou09@gmail.com>
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4372
Differential Revision: D9919677
Pulled By: ajkr
fbshipit-source-id: f74aaa30e2f80e410e299c5a5bca4eaf2a7a26de
Summary:
The code is dead in RocksDB as `log::Reader::initial_offset_` is always zero. We should delete it so we don't have to maintain it like in #4359.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4362
Differential Revision: D9817829
Pulled By: ajkr
fbshipit-source-id: 474a2c679e5bd273b40608f3a5332931d9eefe6d
Summary:
As you know, almost all compilers support "pragma once" keyword instead of using include guards. To be keep consistency between header files, all header files are edited.
Besides this, try to fix some warnings about loss of data.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4339
Differential Revision: D9654990
Pulled By: ajkr
fbshipit-source-id: c2cf3d2d03a599847684bed81378c401920ca848
Summary:
We want to sample the file I/O issued by RocksDB and report the function calls. This requires us to include the file paths otherwise it's hard to tell what has been going on.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4039
Differential Revision: D8670178
Pulled By: riversand963
fbshipit-source-id: 97ee806d1c583a2983e28e213ee764dc6ac28f7a
Summary:
During recovery, RocksDB is able to handle version edits that belong to group commits.
This PR is a subset of [PR 3752](https://github.com/facebook/rocksdb/pull/3752)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3945
Differential Revision: D8529122
Pulled By: riversand963
fbshipit-source-id: 57cb0f9cc55ecca684a837742d6626dc9c07f37e
Summary:
RocksDB used to store global_seqno in external SST files written by
SstFileWriter. During file ingestion, RocksDB uses `pwrite` to update the
`global_seqno`. Since random write is not supported in some non-POSIX compliant
file systems, external SST file ingestion is not supported on these file
systems. To address this limitation, we no longer update `global_seqno` during
file ingestion. Later RocksDB uses the MANIFEST and other information in table
properties to deduce global seqno for externally-ingested SST files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4172
Differential Revision: D8961465
Pulled By: riversand963
fbshipit-source-id: 4382ec85270a96be5bc0cf33758ca2b167b05071
Summary:
Currently in `Version::Get` when reporting ticker stats stored in `GetContext`, there is a big for-loop through all `Ticker` which adds unnecessary cost to overall CPU usage. We can optimize by storing only ticker values that are used in `Get()` calls in a new struct `GetContextStats` since only a small fraction of all tickers are used in `Get()` calls. For comparison, with the new approach we only need to visit 17 values while old approach will require visiting 100+ `Ticker`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3490
Differential Revision: D6969154
Pulled By: miasantreble
fbshipit-source-id: fc27072965a3a94125a3e6883d20dafcf5b84029
Summary:
PR #3944 introduces group commit of `VersionEdit` in MANIFEST. The
implementation has a bug. When updating the log file number of each column
family, we must consider only `VersionEdit`s that operate on the same column
family. Otherwise, a column family may accidentally set its log file number
higher than actual value, indicating that log files with smaller file number
will be ignored, thus causing some updates to be lost.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4157
Differential Revision: D8916650
Pulled By: riversand963
fbshipit-source-id: 8f456cf688f17bf35ad87b38e30e899aa162f201
Summary:
Do not consider the range tombstone sentinel key as causing 2 adjacent
sstables in a level to overlap. When a range tombstone's end key is the
largest key in an sstable, the sstable's end key is so to a "sentinel"
value that is the smallest key in the next sstable with a sequence
number of kMaxSequenceNumber. This "sentinel" is guaranteed to not
overlap in internal-key space with the next sstable. Unfortunately,
GetOverlappingFiles uses user-keys to determine overlap and was thus
considering 2 adjacent sstables in a level to overlap if they were
separated by this sentinel key. This in turn would cause compactions to
be larger than necessary.
Note that this conflicts with
https://github.com/facebook/rocksdb/pull/2769 and cases
`DBRangeDelTest.CompactionTreatsSplitInputLevelDeletionAtomically` to
fail.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4050
Differential Revision: D8844423
Pulled By: ajkr
fbshipit-source-id: df3f9f1db8f4cff2bff77376b98b83c2ae1d155b
Summary:
clang analyze is giving the following warnings:
> db/compaction_job.cc:1178:16: warning: Called C++ object pointer is null
} else if (meta->smallest.size() > 0) {
^~~~~~~~~~~~~~~~~~~~~
db/compaction_job.cc:1201:33: warning: Access to field 'marked_for_compaction' results in a dereference of a null pointer (loaded from variable 'meta')
meta->marked_for_compaction = sub_compact->builder->NeedCompact();
~~~~
db/version_set.cc:2770:26: warning: Called C++ object pointer is null
uint32_t cf_id = last_writer->cfd->GetID();
^~~~~~~~~~~~~~~~~~~~~~~~~
Closes https://github.com/facebook/rocksdb/pull/4072
Differential Revision: D8685852
Pulled By: miasantreble
fbshipit-source-id: b0e2fd9dfc1cbba2317723e09886384b9b1c9085
Summary:
This PR supports the group commit of multiple version edit entries corresponding to different column families. Column family drop/creation still cannot be grouped. This PR is a subset of [PR 3752](https://github.com/facebook/rocksdb/pull/3752).
Closes https://github.com/facebook/rocksdb/pull/3944
Differential Revision: D8432536
Pulled By: riversand963
fbshipit-source-id: 8f11bd05193b6c0d9272d82e44b676abfac113cb
Summary:
https://github.com/facebook/rocksdb/pull/3881 fixed a bug where PinnableSlice pin mmap files which could be deleted with background compaction. This is however a non-issue for ReadOnlyDB when there is no compaction running and max_open_files is -1. This patch reenables the pinning feature for that case.
Closes https://github.com/facebook/rocksdb/pull/4053
Differential Revision: D8662546
Pulled By: maysamyabandeh
fbshipit-source-id: 402962602eb0f644e17822748332999c3af029fd
Summary:
We potentially need this information for tracing, profiling and diagnosis.
Closes https://github.com/facebook/rocksdb/pull/4026
Differential Revision: D8555214
Pulled By: riversand963
fbshipit-source-id: 4263e06c00b6d5410b46aa46eb4e358ff2161dd2
Summary:
The Block object assumes contents are uncompressed. Block's constructor tries to read the number of restarts, but does not get an accurate number when its contents are compressed, which is causing issues like https://github.com/facebook/rocksdb/issues/3843.
This PR address this issue by skipping reconstruction of restart points when blocks are known to be compressed. Somehow the restart points can be read directly when Snappy is used and some tests (for example https://github.com/facebook/rocksdb/blob/master/db/db_block_cache_test.cc#L196) expects blocks to be fully constructed even when Snappy compression is used, so here we keep the restart point logic for Snappy.
Closes https://github.com/facebook/rocksdb/pull/3996
Differential Revision: D8416186
Pulled By: miasantreble
fbshipit-source-id: 002c0b62b9e5d89fb7736563d354ce0023c8cb28
Summary:
Currently it is not possible to change bloom filter config without restart the db, which is causing a lot of operational complexity for users.
This PR aims to make it possible to dynamically change bloom filter config.
Closes https://github.com/facebook/rocksdb/pull/3601
Differential Revision: D7253114
Pulled By: miasantreble
fbshipit-source-id: f22595437d3e0b86c95918c484502de2ceca120c
Summary:
Before this PR, Iterator/InternalIterator may simultaneously have non-ok status() and Valid() = true. That state means that the last operation failed, but the iterator is nevertheless positioned on some unspecified record. Likely intended uses of that are:
* If some sst files are corrupted, a normal iterator can be used to read the data from files that are not corrupted.
* When using read_tier = kBlockCacheTier, read the data that's in block cache, skipping over the data that is not.
However, this behavior wasn't documented well (and until recently the wiki on github had misleading incorrect information). In the code there's a lot of confusion about the relationship between status() and Valid(), and about whether Seek()/SeekToLast()/etc reset the status or not. There were a number of bugs caused by this confusion, both inside rocksdb and in the code that uses rocksdb (including ours).
This PR changes the convention to:
* If status() is not ok, Valid() always returns false.
* Any seek operation resets status. (Before the PR, it depended on iterator type and on particular error.)
This does sacrifice the two use cases listed above, but siying said it's ok.
Overview of the changes:
* A commit that adds missing status checks in MergingIterator. This fixes a bug that actually affects us, and we need it fixed. `DBIteratorTest.NonBlockingIterationBugRepro` explains the scenario.
* Changes to lots of iterator types to make all of them conform to the new convention. Some bug fixes along the way. By far the biggest changes are in DBIter, which is a big messy piece of code; I tried to make it less big and messy but mostly failed.
* A stress-test for DBIter, to gain some confidence that I didn't break it. It does a few million random operations on the iterator, while occasionally modifying the underlying data (like ForwardIterator does) and occasionally returning non-ok status from internal iterator.
To find the iterator types that needed changes I searched for "public .*Iterator" in the code. Here's an overview of all 27 iterator types:
Iterators that didn't need changes:
* status() is always ok(), or Valid() is always false: MemTableIterator, ModelIter, TestIterator, KVIter (2 classes with this name anonymous namespaces), LoggingForwardVectorIterator, VectorIterator, MockTableIterator, EmptyIterator, EmptyInternalIterator.
* Thin wrappers that always pass through Valid() and status(): ArenaWrappedDBIter, TtlIterator, InternalIteratorFromIterator.
Iterators with changes (see inline comments for details):
* DBIter - an overhaul:
- It used to silently skip corrupted keys (`FindParseableKey()`), which seems dangerous. This PR makes it just stop immediately after encountering a corrupted key, just like it would for other kinds of corruption. Let me know if there was actually some deeper meaning in this behavior and I should put it back.
- It had a few code paths silently discarding subiterator's status. The stress test caught a few.
- The backwards iteration code path was expecting the internal iterator's set of keys to be immutable. It's probably always true in practice at the moment, since ForwardIterator doesn't support backwards iteration, but this PR fixes it anyway. See added DBIteratorTest.ReverseToForwardBug for an example.
- Some parts of backwards iteration code path even did things like `assert(iter_->Valid())` after a seek, which is never a safe assumption.
- It used to not reset status on seek for some types of errors.
- Some simplifications and better comments.
- Some things got more complicated from the added error handling. I'm open to ideas for how to make it nicer.
* MergingIterator - check status after every operation on every subiterator, and in some places assert that valid subiterators have ok status.
* ForwardIterator - changed to the new convention, also slightly simplified.
* ForwardLevelIterator - fixed some bugs and simplified.
* LevelIterator - simplified.
* TwoLevelIterator - changed to the new convention. Also fixed a bug that would make SeekForPrev() sometimes silently ignore errors from first_level_iter_.
* BlockBasedTableIterator - minor changes.
* BlockIter - replaced `SetStatus()` with `Invalidate()` to make sure non-ok BlockIter is always invalid.
* PlainTableIterator - some seeks used to not reset status.
* CuckooTableIterator - tiny code cleanup.
* ManagedIterator - fixed some bugs.
* BaseDeltaIterator - changed to the new convention and fixed a bug.
* BlobDBIterator - seeks used to not reset status.
* KeyConvertingIterator - some small change.
Closes https://github.com/facebook/rocksdb/pull/3810
Differential Revision: D7888019
Pulled By: al13n321
fbshipit-source-id: 4aaf6d3421c545d16722a815b2fa2e7912bc851d
Summary:
This patch record min log number to keep to the manifest while flushing SST files to ignore them and any WAL older than them during recovery. This is to avoid scenarios when we have a gap between the WAL files are fed to the recovery procedure. The gap could happen by for example out-of-order WAL deletion. Such gap could cause problems in 2PC recovery where the prepared and commit entry are placed into two separate WAL and gap in the WALs could result into not processing the WAL with the commit entry and hence breaking the 2PC recovery logic.
Before the commit, for 2PC case, we determined which log number to keep in FindObsoleteFiles(). We looked at the earliest logs with outstanding prepare entries, or prepare entries whose respective commit or abort are in memtable. With the commit, the same calculation is done while we apply the SST flush. Just before installing the flush file, we precompute the earliest log file to keep after the flush finishes using the same logic (but skipping the memtables just flushed), record this information to the manifest entry for this new flushed SST file. This pre-computed value is also remembered in memory, and will later be used to determine whether a log file can be deleted. This value is unlikely to change until next flush because the commit entry will stay in memtable. (In WritePrepared, we could have removed the older log files as soon as all prepared entries are committed. It's not yet done anyway. Even if we do it, the only thing we loss with this new approach is earlier log deletion between two flushes, which does not guarantee to happen anyway because the obsolete file clean-up function is only executed after flush or compaction)
This min log number to keep is stored in the manifest using the safely-ignore customized field of AddFile entry, in order to guarantee that the DB generated using newer release can be opened by previous releases no older than 4.2.
Closes https://github.com/facebook/rocksdb/pull/3765
Differential Revision: D7747618
Pulled By: siying
fbshipit-source-id: d00c92105b4f83852e9754a1b70d6b64cb590729
Summary:
This reverts commit 73f21a7b21.
It breaks compatibility. When created a DB using a build with this new change, opening the DB and reading the data will fail with this error:
"Corruption: Can't access /000000.sst: IO error: while stat a file for size: /tmp/xxxx/000000.sst: No such file or directory"
This is because the dummy AddFile4 entry generated by the new code will be treated as a real entry by an older build. The older build will think there is a real file with number 0, but there isn't such a file.
Closes https://github.com/facebook/rocksdb/pull/3762
Differential Revision: D7730035
Pulled By: siying
fbshipit-source-id: f2051859eff20ef1837575ecb1e1bb96b3751e77
Summary:
This PR comments out the rest of the unused arguments which allow us to turn on the -Wunused-parameter flag. This is the second part of a codemod relating to https://github.com/facebook/rocksdb/pull/3557.
Closes https://github.com/facebook/rocksdb/pull/3662
Differential Revision: D7426121
Pulled By: Dayvedde
fbshipit-source-id: 223994923b42bd4953eb016a0129e47560f7e352
Summary:
In this change, an option to set different paths for different column families is added.
This option is set via cf_paths setting of ColumnFamilyOptions. This option will work in a similar fashion to db_paths setting. Cf_paths is a vector of Dbpath values which contains a pair of the absolute path and target size. Multiple levels in a Column family can go to different paths if cf_paths has more than one path.
To maintain backward compatibility, if cf_paths is not specified for a column family, db_paths setting will be used. Note that, if db_paths setting is also not specified, RocksDB already has code to use db_name as the only path.
Changes :
1) A new member "cf_paths" is added to ImmutableCfOptions. This is set, based on cf_paths setting of ColumnFamilyOptions and db_paths setting of ImmutableDbOptions. This member is used to identify the path information whenever files are accessed.
2) Validation checks are added for cf_paths setting based on existing checks for db_paths setting.
3) DestroyDB, PurgeObsoleteFiles etc. are edited to support multiple cf_paths.
4) Unit tests are added appropriately.
Closes https://github.com/facebook/rocksdb/pull/3102
Differential Revision: D6951697
Pulled By: ajkr
fbshipit-source-id: 60d2262862b0a8fd6605b09ccb0da32bb331787d
Summary:
Level Compaction with TTL.
As of today, a file could exist in the LSM tree without going through the compaction process for a really long time if there are no updates to the data in the file's key range. For example, in certain use cases, the keys are not actually "deleted"; instead they are just set to empty values. There might not be any more writes to this "deleted" key range, and if so, such data could remain in the LSM for a really long time resulting in wasted space.
Introducing a TTL could solve this problem. Files (and, in turn, data) older than TTL will be scheduled for compaction when there is no other background work. This will make the data go through the regular compaction process and get rid of old unwanted data.
This also has the (good) side-effect of all the data in the non-bottommost level being newer than ttl, and all data in the bottommost level older than ttl. It could lead to more writes while reducing space.
This functionality can be controlled by the newly introduced column family option -- ttl.
TODO for later:
- Make ttl mutable
- Extend TTL to Universal compaction as well? (TTL is already supported in FIFO)
- Maybe deprecate CompactionOptionsFIFO.ttl in favor of this new ttl option.
Closes https://github.com/facebook/rocksdb/pull/3591
Differential Revision: D7275442
Pulled By: sagar0
fbshipit-source-id: dcba484717341200d419b0953dafcdf9eb2f0267
Summary:
This patch record the deleted WAL numbers in the manifest to ignore them and any WAL older than them during recovery. This is to avoid scenarios when we have a gap between the WAL files are fed to the recovery procedure. The gap could happen by for example out-of-order WAL deletion. Such gap could cause problems in 2PC recovery where the prepared and commit entry are placed into two separate WAL and gap in the WALs could result into not processing the WAL with the commit entry and hence breaking the 2PC recovery logic.
Closes https://github.com/facebook/rocksdb/pull/3488
Differential Revision: D6967893
Pulled By: maysamyabandeh
fbshipit-source-id: 13119feb155a08ab6d4909f437c7a750480dc8a1
Summary:
If there are a lot of overlapped files in L0, creating a merging iterator for
all files in L0 to check overlap can be very slow because we need to read and
seek all files in L0. However, in that case, the ingested file is likely to
overlap with some files in L0, so if we check those files one by one, we can stop
once we encounter overlap.
Ref: https://github.com/facebook/rocksdb/issues/3540
Closes https://github.com/facebook/rocksdb/pull/3564
Differential Revision: D7196784
Pulled By: anand1976
fbshipit-source-id: 8700c1e903bd515d0fa7005b6ce9b3a3d9db2d67
Summary:
Add "rocksdb.live-sst-files-size" DB property which only include files of latest version. Existing "rocksdb.total-sst-files-size" include files from all versions and thus include files that's obsolete but not yet deleted. I'm going to use this new property to cap blob db sst + blob files size.
Closes https://github.com/facebook/rocksdb/pull/3548
Differential Revision: D7116939
Pulled By: yiwu-arbug
fbshipit-source-id: c6a52e45ce0f24ef78708156e1a923c1dd6bc79a
Summary:
Use a customzied BlockBasedTableIterator and LevelIterator to replace current implementations leveraging two-level-iterator. Hope the customized logic will make code easier to understand. As a side effect, BlockBasedTableIterator reduces the allocation for the data block iterator object, and avoid the virtual function call to it, because we can directly reference BlockIter, a final class. Similarly, LevelIterator reduces virtual function call to the dummy iterator iterating the file metadata. It also enabled further optimization.
The upper bound check is also moved from index block to data block. This implementation fits this iterator better. After the change, forwared iterator is slightly optimized to ensure we trim those iterators.
The two-level-iterator now is only used by partitioned index, so it is simplified.
Closes https://github.com/facebook/rocksdb/pull/3406
Differential Revision: D6809041
Pulled By: siying
fbshipit-source-id: 7da3b9b1d3c8e9d9405302c15920af1fcaf50ffa
Summary:
db/version_builder.cc:
117 base_vstorage_->InternalComparator();
CID 1351713 (#1 of 1): Uninitialized pointer field (UNINIT_CTOR)
2. uninit_member: Non-static class member field level_zero_cmp_.internal_comparator is not initialized in this constructor nor in any functions that it calls.
db/version_edit.h:
145 FdWithKeyRange()
146 : fd(),
147 smallest_key(),
148 largest_key() {
CID 1418254 (#1 of 1): Uninitialized pointer field (UNINIT_CTOR)
2. uninit_member: Non-static class member file_metadata is not initialized in this constructor nor in any functions that it calls.
149 }
db/version_set.cc:
120 }
CID 1322789 (#1 of 1): Uninitialized pointer field (UNINIT_CTOR)
4. uninit_member: Non-static class member curr_file_level_ is not initialized in this constructor nor in any functions that it calls.
121 }
db/write_batch.cc:
939 assert(cf_mems_);
CID 1419862 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR)
3. uninit_member: Non-static class member rebuilding_trx_seq_ is not initialized in this constructor nor in any functions that it calls.
940 }
Closes https://github.com/facebook/rocksdb/pull/3092
Differential Revision: D6505666
Pulled By: yiwu-arbug
fbshipit-source-id: fd2c68948a0280772691a419d72ac7e190951d86
Summary:
Fix for #2833.
- In `DeleteFilesInRange`, use `GetCleanInputsWithinInterval` instead of `GetOverlappingInputs` to make sure we get a clean cut set of files to delete.
- In `GetCleanInputsWithinInterval`, support nullptr as `begin_key` or `end_key`.
- In `GetOverlappingInputsRangeBinarySearch`, move the assertion for non-empty range away from `ExtendFileRangeWithinInterval`, which should be allowed to return an empty range (via `end_index < begin_index`).
Closes https://github.com/facebook/rocksdb/pull/2843
Differential Revision: D5772387
Pulled By: ajkr
fbshipit-source-id: e554e8461823c6be82b21a9262a2da02b3957881
Summary:
Add PreReleaseCallback to be called at the end of WriteImpl but before publishing the sequence number. The callback is used in WritePrepareTxn to i) update the commit map, ii) update the last published sequence number in the 2nd write queue. It also ensures that all the commits will go to the 2nd queue.
These changes will ensure that the commit map is updated before the sequence number is published and used by reading snapshots. If we use two write queues, the snapshots will use the seq number published by the 2nd queue. If we use one write queue (the default, the snapshots will use the last seq number in the memtable, which also indicates the last published seq number.
Closes https://github.com/facebook/rocksdb/pull/3205
Differential Revision: D6438959
Pulled By: maysamyabandeh
fbshipit-source-id: f8b6c434e94bc5f5ab9cb696879d4c23e2577ab9
Summary:
Before we were checking every file in the level which was unnecessary. We can piggyback onto the code for checking point-key overlap, which already opens all the files that could possibly contain overlapping range deletions. This PR makes us check just the range deletions from those files, so no extra ones will be opened.
Closes https://github.com/facebook/rocksdb/pull/3179
Differential Revision: D6358125
Pulled By: ajkr
fbshipit-source-id: 00e200770fdb8f3cc6b1b2da232b755e4ba36279
Summary:
When snapshots are held for a long time, files may reach the bottom level containing overwritten/deleted keys. We previously had no mechanism to trigger compaction on such files. This particularly impacted DBs that write to different parts of the keyspace over time, as such files would never be naturally compacted due to second-last level files moving down. This PR introduces a mechanism for bottommost files to be recompacted upon releasing all snapshots that prevent them from dropping their deleted/overwritten keys.
- Changed `CompactionPicker` to compact files in `BottommostFilesMarkedForCompaction()`. These are the last choice when picking. Each file will be compacted alone and output to the same level in which it originated. The goal of this type of compaction is to rewrite the data excluding deleted/overwritten keys.
- Changed `ReleaseSnapshot()` to recompute the bottom files marked for compaction when the oldest existing snapshot changes, and schedule a compaction if needed. We cache the value that oldest existing snapshot needs to exceed in order for another file to be marked in `bottommost_files_mark_threshold_`, which allows us to avoid recomputing marked files for most snapshot releases.
- Changed `VersionStorageInfo` to track the list of bottommost files, which is recomputed every time the version changes by `UpdateBottommostFiles()`. The list of marked bottommost files is first computed in `ComputeBottommostFilesMarkedForCompaction()` when the version changes, but may also be recomputed when `ReleaseSnapshot()` is called.
- Extracted core logic of `Compaction::IsBottommostLevel()` into `VersionStorageInfo::RangeMightExistAfterSortedRun()` since logic to check whether a file is bottommost is now necessary outside of compaction.
Closes https://github.com/facebook/rocksdb/pull/3009
Differential Revision: D6062044
Pulled By: ajkr
fbshipit-source-id: 123d201cf140715a7d5928e8b3cb4f9cd9f7ad21
Summary:
MSVC does not support unused attribute at this time. A separate assignment line fixes the issue probably by being counted as usage for MSVC and it no longer complains about unused var.
Closes https://github.com/facebook/rocksdb/pull/3048
Differential Revision: D6126272
Pulled By: maysamyabandeh
fbshipit-source-id: 4907865db45fd75a39a15725c0695aaa17509c1f
Summary:
ColumnFamilyOptions::compaction_options_fifo and all its sub-fields can be set dynamically now.
Some of the ways in which the fifo compaction options can be set are:
- `SetOptions({{"compaction_options_fifo", "{max_table_files_size=1024}"}})`
- `SetOptions({{"compaction_options_fifo", "{ttl=600;}"}})`
- `SetOptions({{"compaction_options_fifo", "{max_table_files_size=1024;ttl=600;}"}})`
- `SetOptions({{"compaction_options_fifo", "{max_table_files_size=51;ttl=49;allow_compaction=true;}"}})`
Most of the code has been made generic enough so that it could be reused later to make universal options (and other such nested defined-types) dynamic with very few lines of parsing/serializing code changes.
Introduced a few new functions like `ParseStruct`, `SerializeStruct` and `GetStringFromStruct`.
The duplicate code in `GetStringFromDBOptions` and `GetStringFromColumnFamilyOptions` has been moved into `GetStringFromStruct`. So they become just simple wrappers now.
Closes https://github.com/facebook/rocksdb/pull/3006
Differential Revision: D6058619
Pulled By: sagar0
fbshipit-source-id: 1e8f78b3374ca5249bb4f3be8a6d3bb4cbc52f92
Summary:
The file numbers assigned post-repair were sometimes smaller than older files' numbers due to `LogAndApply` saving the wrong next file number in the manifest.
- Mark the highest file seen during repair as used before `LogAndApply` so the correct next file number will be stored.
- Renamed `MarkFileNumberUsedDuringRecovery` to `MarkFileNumberUsed` since now it's used during repair in addition to during recovery
- Added `TEST_Current_Next_FileNo` to expose the next file number for the unit test.
Closes https://github.com/facebook/rocksdb/pull/2988
Differential Revision: D6018083
Pulled By: ajkr
fbshipit-source-id: 3f25cbf74439cb8f16dd12af90b67f9f9f75e718
Summary:
Add kTypeBlobIndex value type, which will be used by blob db only, to insert a (key, blob_offset) KV pair. The purpose is to
1. Make it possible to open existing rocksdb instance as blob db. Existing value will be of kTypeIndex type, while value inserted by blob db will be of kTypeBlobIndex.
2. Make rocksdb able to detect if the db contains value written by blob db, if so return error.
3. Make it possible to have blob db optionally store value in SST file (with kTypeValue type) or as a blob value (with kTypeBlobIndex type).
The root db (DBImpl) basically pretended kTypeBlobIndex are normal value on write. On Get if is_blob is provided, return whether the value read is of kTypeBlobIndex type, or return Status::NotSupported() status if is_blob is not provided. On scan allow_blob flag is pass and if the flag is true, return wether the value is of kTypeBlobIndex type via iter->IsBlob().
Changes on blob db side will be in a separate patch.
Closes https://github.com/facebook/rocksdb/pull/2886
Differential Revision: D5838431
Pulled By: yiwu-arbug
fbshipit-source-id: 3c5306c62bc13bb11abc03422ec5cbcea1203cca
Summary:
Recover txns from the WAL. Also added some unit tests.
Closes https://github.com/facebook/rocksdb/pull/2901
Differential Revision: D5859596
Pulled By: maysamyabandeh
fbshipit-source-id: 6424967b231388093b4effffe0a3b1b7ec8caeb0
Summary:
- Switched all instances of SetMinPossibleForUserKey and SetMaxPossibleForUserKey in accordance to InternalKeyComparator's comparison logic
Closes https://github.com/facebook/rocksdb/pull/2868
Differential Revision: D5804152
Pulled By: axxufb
fbshipit-source-id: 80be35e04f2e8abc35cc64abe1fecb03af24e183
Summary:
This patch instruments the read path to verify each read value against an optional ReadCallback class. If the value is rejected, the reader moves on to the next value. The WritePreparedTxn makes use of this feature to skip sequence numbers that are not in the read snapshot.
Closes https://github.com/facebook/rocksdb/pull/2850
Differential Revision: D5787375
Pulled By: maysamyabandeh
fbshipit-source-id: 49d808b3062ab35e7ae98ad388f659757794184c
Summary:
Allow user to reduce number of levels in LSM by issue a full CompactRange() and put the result in a lower level, and then reopen DB with reduced options.num_levels. Previous this will fail on reopen on when recovery replaying the previous MANIFEST and found a historical file was on a higher level than the new options.num_levels. The workaround was after CompactRange(), reopen the DB with old num_levels, which will create a new MANIFEST, and then reopen the DB again with new num_levels.
This patch relax the check of levels during recovery. It allows DB to open if there was a historical file on level > options.num_levels, but was also deleted.
Closes https://github.com/facebook/rocksdb/pull/2740
Differential Revision: D5629354
Pulled By: yiwu-arbug
fbshipit-source-id: 545903f6b36b6083e8cbaf777176aef2f488021d
Summary:
When we had a single thread pool for compactions, a thread could be busy for a long time (minutes) executing a compaction involving the bottom level. In multi-instance setups, the entire thread pool could be consumed by such bottom-level compactions. Then, top-level compactions (e.g., a few L0 files) would be blocked for a long time ("head-of-line blocking"). Such top-level compactions are critical to prevent compaction stalls as they can quickly reduce number of L0 files / sorted runs.
This diff introduces a bottom-priority queue for universal compactions including the bottom level. This alleviates the head-of-line blocking situation for fast, top-level compactions.
- Added `Env::Priority::BOTTOM` thread pool. This feature is only enabled if user explicitly configures it to have a positive number of threads.
- Changed `ThreadPoolImpl`'s default thread limit from one to zero. This change is invisible to users as we call `IncBackgroundThreadsIfNeeded` on the low-pri/high-pri pools during `DB::Open` with values of at least one. It is necessary, though, for bottom-pri to start with zero threads so the feature is disabled by default.
- Separated `ManualCompaction` into two parts in `PrepickedCompaction`. `PrepickedCompaction` is used for any compaction that's picked outside of its execution thread, either manual or automatic.
- Forward universal compactions involving last level to the bottom pool (worker thread's entry point is `BGWorkBottomCompaction`).
- Track `bg_bottom_compaction_scheduled_` so we can wait for bottom-level compactions to finish. We don't count them against the background jobs limits. So users of this feature will get an extra compaction for free.
Closes https://github.com/facebook/rocksdb/pull/2580
Differential Revision: D5422916
Pulled By: ajkr
fbshipit-source-id: a74bd11f1ea4933df3739b16808bb21fcd512333
Summary:
Breaking commit: d12691b86f
In the above commit, I moved the `TableCache` cleanup logic from `Version` destructor into `PurgeObsoleteFiles`. I missed cleaning up `TableCache` entries for the current `Version` during DB destruction.
This PR adds that logic to `VersionSet` destructor. One unfortunate side effect is now we're potentially deleting `TableReader`s after `column_family_set_.reset()`, which means we can't call `BlockBasedTableReader::Close` a second time as the block cache might already be destroyed.
Closes https://github.com/facebook/rocksdb/pull/2662
Differential Revision: D5515108
Pulled By: ajkr
fbshipit-source-id: 2cb820e19aa813e0d258d17f76b2d7b6b7ee0b18
Summary:
Post-compaction work holds onto db mutex for the longest time (found by tracing lock acquires/releases with LTTng and correlating timestamps with our info log). Further experimentation showed `TableCache::EraseHandle` is responsible for ~86% of time mutex is held. We can just release the handle outside the db mutex.
Closes https://github.com/facebook/rocksdb/pull/2654
Differential Revision: D5507126
Pulled By: ajkr
fbshipit-source-id: 703c01ddf2aea16bc0f9e33c08935d78aa6b781d
Summary:
This reverts the previous commit 1d7048c598, which broke the build.
Did a `git revert 1d7048c`.
Closes https://github.com/facebook/rocksdb/pull/2627
Differential Revision: D5476473
Pulled By: sagar0
fbshipit-source-id: 4756ff5c0dfc88c17eceb00e02c36176de728d06
Summary: This uses `clang-tidy` to comment out unused parameters (in functions, methods and lambdas) in fbcode. Cases that the tool failed to handle are fixed manually.
Reviewed By: igorsugak
Differential Revision: D5454343
fbshipit-source-id: 5dee339b4334e25e963891b519a5aa81fbf627b2
Summary:
We've got some DBs where iterators return Status with message "Corruption: block checksum mismatch" all the time. That's not very informative. It would be much easier to investigate if the error message contained the file name - then we would know e.g. how old the corrupted file is, which would be very useful for finding the root cause. This PR adds file name, offset and other stuff to some block corruption-related status messages.
It doesn't improve all the error messages, just a few that were easy to improve. I'm mostly interested in "block checksum mismatch" and "Bad table magic number" since they're the only corruption errors that I've ever seen in the wild.
Closes https://github.com/facebook/rocksdb/pull/2507
Differential Revision: D5345702
Pulled By: al13n321
fbshipit-source-id: fc8023d43f1935ad927cef1b9c55481ab3cb1339
Summary:
Introducing FIFO compactions with TTL.
FIFO compaction is based on size only which makes it tricky to enable in production as use cases can have organic growth. A user requested an option to drop files based on the time of their creation instead of the total size.
To address that request:
- Added a new TTL option to FIFO compaction options.
- Updated FIFO compaction score to take TTL into consideration.
- Added a new table property, creation_time, to keep track of when the SST file is created.
- Creation_time is set as below:
- On Flush: Set to the time of flush.
- On Compaction: Set to the max creation_time of all the files involved in the compaction.
- On Repair and Recovery: Set to the time of repair/recovery.
- Old files created prior to this code change will have a creation_time of 0.
- FIFO compaction with TTL is enabled when ttl > 0. All files older than ttl will be deleted during compaction. i.e. `if (file.creation_time < (current_time - ttl)) then delete(file)`. This will enable cases where you might want to delete all files older than, say, 1 day.
- FIFO compaction will fall back to the prior way of deleting files based on size if:
- the creation_time of all files involved in compaction is 0.
- the total size (of all SST files combined) does not drop below `compaction_options_fifo.max_table_files_size` even if the files older than ttl are deleted.
This feature is not supported if max_open_files != -1 or with table formats other than Block-based.
**Test Plan:**
Added tests.
**Benchmark results:**
Base: FIFO with max size: 100MB ::
```
svemuri@dev15905 ~/rocksdb (fifo-compaction) $ TEST_TMPDIR=/dev/shm ./db_bench --benchmarks=readwhilewriting --num=5000000 --threads=16 --compaction_style=2 --fifo_compaction_max_table_files_size_mb=100
readwhilewriting : 1.924 micros/op 519858 ops/sec; 13.6 MB/s (1176277 of 5000000 found)
```
With TTL (a low one for testing) ::
```
svemuri@dev15905 ~/rocksdb (fifo-compaction) $ TEST_TMPDIR=/dev/shm ./db_bench --benchmarks=readwhilewriting --num=5000000 --threads=16 --compaction_style=2 --fifo_compaction_max_table_files_size_mb=100 --fifo_compaction_ttl=20
readwhilewriting : 1.902 micros/op 525817 ops/sec; 13.7 MB/s (1185057 of 5000000 found)
```
Example Log lines:
```
2017/06/26-15:17:24.609249 7fd5a45ff700 (Original Log Time 2017/06/26-15:17:24.609177) [db/compaction_picker.cc:1471] [default] FIFO compaction: picking file 40 with creation time 1498515423 for deletion
2017/06/26-15:17:24.609255 7fd5a45ff700 (Original Log Time 2017/06/26-15:17:24.609234) [db/db_impl_compaction_flush.cc:1541] [default] Deleted 1 files
...
2017/06/26-15:17:25.553185 7fd5a61a5800 [DEBUG] [db/db_impl_files.cc:309] [JOB 0] Delete /dev/shm/dbbench/000040.sst type=2 #40 -- OK
2017/06/26-15:17:25.553205 7fd5a61a5800 EVENT_LOG_v1 {"time_micros": 1498515445553199, "job": 0, "event": "table_file_deletion", "file_number": 40}
```
SST Files remaining in the dbbench dir, after db_bench execution completed:
```
svemuri@dev15905 ~/rocksdb (fifo-compaction) $ ls -l /dev/shm//dbbench/*.sst
-rw-r--r--. 1 svemuri users 30749887 Jun 26 15:17 /dev/shm//dbbench/000042.sst
-rw-r--r--. 1 svemuri users 30768779 Jun 26 15:17 /dev/shm//dbbench/000044.sst
-rw-r--r--. 1 svemuri users 30757481 Jun 26 15:17 /dev/shm//dbbench/000046.sst
```
Closes https://github.com/facebook/rocksdb/pull/2480
Differential Revision: D5305116
Pulled By: sagar0
fbshipit-source-id: 3e5cfcf5dd07ed2211b5b37492eb235b45139174
Summary:
Throughput: 46k tps in our sysbench settings (filling the details later)
The idea is to have the simplest change that gives us a reasonable boost
in 2PC throughput.
Major design changes:
1. The WAL file internal buffer is not flushed after each write. Instead
it is flushed before critical operations (WAL copy via fs) or when
FlushWAL is called by MySQL. Flushing the WAL buffer is also protected
via mutex_.
2. Use two sequence numbers: last seq, and last seq for write. Last seq
is the last visible sequence number for reads. Last seq for write is the
next sequence number that should be used to write to WAL/memtable. This
allows to have a memtable write be in parallel to WAL writes.
3. BatchGroup is not used for writes. This means that we can have
parallel writers which changes a major assumption in the code base. To
accommodate for that i) allow only 1 WriteImpl that intends to write to
memtable via mem_mutex_--which is fine since in 2PC almost all of the memtable writes
come via group commit phase which is serial anyway, ii) make all the
parts in the code base that assumed to be the only writer (via
EnterUnbatched) to also acquire mem_mutex_, iii) stat updates are
protected via a stat_mutex_.
Note: the first commit has the approach figured out but is not clean.
Submitting the PR anyway to get the early feedback on the approach. If
we are ok with the approach I will go ahead with this updates:
0) Rebase with Yi's pipelining changes
1) Currently batching is disabled by default to make sure that it will be
consistent with all unit tests. Will make this optional via a config.
2) A couple of unit tests are disabled. They need to be updated with the
serial commit of 2PC taken into account.
3) Replacing BatchGroup with mem_mutex_ got a bit ugly as it requires
releasing mutex_ beforehand (the same way EnterUnbatched does). This
needs to be cleaned up.
Closes https://github.com/facebook/rocksdb/pull/2345
Differential Revision: D5210732
Pulled By: maysamyabandeh
fbshipit-source-id: 78653bd95a35cd1e831e555e0e57bdfd695355a4
Summary:
CreateColumnFamily() releases DB mutex after adding column family to the set and install super version (to write option file), so if users call GetAggregatedIntProperty() in the middle, then super version will be null and the process will crash. Fix it by skipping those column families without super version installed.
Maybe we should also fix the problem of releasing the lock when reading option file, but it is more risky. so I'm doing a quick and safer fix and we can investigate it later.
Closes https://github.com/facebook/rocksdb/pull/2475
Differential Revision: D5298053
Pulled By: siying
fbshipit-source-id: 4b3c8f91c60400b163fcc6cda8a0c77723be0ef6
Summary:
We estimate number of reads per SST files, by updating the counter per file in sampled read requests. This information can later be used to trigger compactions to improve read performacne.
Closes https://github.com/facebook/rocksdb/pull/2417
Differential Revision: D5193528
Pulled By: siying
fbshipit-source-id: b4241c5ad0eaf444b61afb53f8e6290d9f5da2df
Summary:
Fixes the following scenario:
1. Set prefix extractor. Enable bloom filters, with `whole_key_filtering = false`. Use compaction filter that sometimes returns `kRemoveAndSkipUntil`.
2. Do a compaction.
3. Compaction creates an iterator with `total_order_seek = false`, calls `SeekToFirst()` on it, then repeatedly calls `Next()`.
4. At some point compaction filter returns `kRemoveAndSkipUntil`.
5. Compaction calls `Seek(skip_until)` on the iterator. The key that it seeks to happens to have prefix that doesn't match the bloom filter. Since `total_order_seek = false`, iterator becomes invalid, and compaction thinks that it has reached the end. The rest of the compaction input is silently discarded.
The fix is to make compaction iterator use `total_order_seek = true`.
The implementation for PlainTable is quite awkward. I've made `kRemoveAndSkipUntil` officially incompatible with PlainTable. If you try to use them together, compaction will fail, and DB will enter read-only mode (`bg_error_`). That's not a very graceful way to communicate a misconfiguration, but the alternatives don't seem worth the implementation time and complexity. To be able to check in advance that `kRemoveAndSkipUntil` is not going to be used with PlainTable, we'd need to extend the interface of either `CompactionFilter` or `InternalIterator`. It seems unlikely that anyone will ever want to use `kRemoveAndSkipUntil` with PlainTable: PlainTable probably has very few users, and `kRemoveAndSkipUntil` has only one user so far: us (logdevice).
Closes https://github.com/facebook/rocksdb/pull/2349
Differential Revision: D5110388
Pulled By: lightmark
fbshipit-source-id: ec29101a99d9dcd97db33923b87f72bce56cc17a
Summary:
The range deletion meta-block iterators weren't getting cleaned up properly since they don't support arena allocation. I didn't implement arena support since, in the general case, each iterator is used only once and separately from all other iterators, so there should be no benefit to data locality.
Anyways, this diff fixes up #2370 by treating range deletion iterators as non-arena-allocated.
Closes https://github.com/facebook/rocksdb/pull/2399
Differential Revision: D5171119
Pulled By: ajkr
fbshipit-source-id: bef6f5c4c5905a124f4993945aed4bd86e2807d8
Summary:
also changed the `>` in the comparison against `level0_file_num_compaction_trigger` into a `>=` since exactly `level0_file_num_compaction_trigger` can trigger a compaction from L0.
Closes https://github.com/facebook/rocksdb/pull/2179
Differential Revision: D4915772
Pulled By: ajkr
fbshipit-source-id: e38fec6253de6f9a40e61734615c6670d84038aa
Summary:
Previously we returned NotSupported when ingesting files into a database containing any range deletions. This diff adds the support.
- Flush if any memtable contains range deletions overlapping the to-be-ingested file
- Place to-be-ingested file before any level that contains range deletions overlapping it.
- Added support for `Version` to return iterators over range deletions in a given level. Previously, we piggybacked getting range deletions onto `Version`'s `Get()` / `AddIterator()` functions by passing them a `RangeDelAggregator*`. But file ingestion needs to get iterators over range deletions, not populate an aggregator (since the aggregator does collapsing and doesn't expose the actual ranges).
Closes https://github.com/facebook/rocksdb/pull/2370
Differential Revision: D5127648
Pulled By: ajkr
fbshipit-source-id: 816faeb9708adfa5287962bafdde717db56e3f1a
Summary:
Add a histogram in statistics to help users understand how many merge operands they merge.
Closes https://github.com/facebook/rocksdb/pull/2373
Differential Revision: D5139983
Pulled By: siying
fbshipit-source-id: 61b9ba8ca83f358530a4833d68f0103b56a0e182
Summary:
Disable direct reads for log and manifest. Direct reads should not affect sequential_file
Also add kDirectIO for option_config_ in db_test_util
Closes https://github.com/facebook/rocksdb/pull/2337
Differential Revision: D5100261
Pulled By: lightmark
fbshipit-source-id: 0ebfd13b93fa1b8f9acae514ac44f8125a05868b
Summary:
Now if we have iterate_upper_bound set, we continue read until get a key >= upper_bound. For a lot of cases that neighboring data blocks have a user key gap between them, our index key will be a user key in the middle to get a shorter size. For example, if we have blocks:
[a b c d][f g h]
Then the index key for the first block will be 'e'.
then if upper bound is any key between 'd' and 'e', for example, d1, d2, ..., d99999999999, we don't have to read the second block and also know that we have done our iteration by reaching the last key that smaller the upper bound already.
This diff can reduce RA in most cases.
Closes https://github.com/facebook/rocksdb/pull/2239
Differential Revision: D4990693
Pulled By: lightmark
fbshipit-source-id: ab30ea2e3c6edf3fddd5efed3c34fcf7739827ff
Summary:
Allow an option for users to do some compaction in FIFO compaction, to pay some write amplification for fewer number of files.
Closes https://github.com/facebook/rocksdb/pull/2163
Differential Revision: D4895953
Pulled By: siying
fbshipit-source-id: a1ab608dd0627211f3e1f588a2e97159646e1231
Summary:
Changed dynamic leveling to stop setting the base level's size bound below `max_bytes_for_level_base`.
Behavior for config where `max_bytes_for_level_base == level0_file_num_compaction_trigger * write_buffer_size` and same amount of data in L0 and base-level:
- Before #2027, compaction scoring would favor base-level due to dividing by size smaller than `max_bytes_for_level_base`.
- After #2027, L0 and Lbase get equal scores. The disadvantage is L0 is often compacted before reaching the num files trigger since `write_buffer_size` can be bigger than the dynamically chosen base-level size. This increases write-amp.
- After this diff, L0 and Lbase still get equal scores. Now it takes `level0_file_num_compaction_trigger` files of size `write_buffer_size` to trigger L0 compaction by size, fixing the write-amp problem above.
Closes https://github.com/facebook/rocksdb/pull/2123
Differential Revision: D4861570
Pulled By: ajkr
fbshipit-source-id: 467ddef56ed1f647c14d86bb018bcb044c39b964
Summary:
Makes max_open_files db option dynamically set-able by SetDBOptions. During the call of SetDBOptions we call SetCapacity on the table cache, which is a LRUCache.
Closes https://github.com/facebook/rocksdb/pull/2185
Differential Revision: D4979189
Pulled By: yiwu-arbug
fbshipit-source-id: ca7e8dc5e3619c79434f579be4847c0f7e56afda
Summary:
The goal is to avoid the problem of small number of L0 files triggering compaction to base level (which increased write-amp), while still allowing L0 compaction-by-size (so intra-L0 compactions cause score to increase).
Closes https://github.com/facebook/rocksdb/pull/2172
Differential Revision: D4908552
Pulled By: ajkr
fbshipit-source-id: 4b170142b2b368e24bd7948b2a6f24c69fabf73d
Summary:
Replace Options::use_direct_writes with Options::use_direct_io_for_flush_and_compaction
Now if Options::use_direct_io_for_flush_and_compaction = true, we will enable direct io for both reads and writes for flush and compaction job. Whereas Options::use_direct_reads controls user reads like iterator and Get().
Closes https://github.com/facebook/rocksdb/pull/2117
Differential Revision: D4860912
Pulled By: lightmark
fbshipit-source-id: d93575a8a5e780cf7e40797287edc425ee648c19
Summary:
This is an effort to club all string related utility functions into one common place, in string_util, so that it is easier for everyone to know what string processing functions are available. Right now they seem to be spread out across multiple modules, like logging and options_helper.
Check the sub-commits for easier reviewing.
Closes https://github.com/facebook/rocksdb/pull/2094
Differential Revision: D4837730
Pulled By: sagar0
fbshipit-source-id: 344278a
Summary:
Move some files under util/ to new directories env/, monitoring/ options/ and cache/
Closes https://github.com/facebook/rocksdb/pull/2090
Differential Revision: D4833681
Pulled By: siying
fbshipit-source-id: 2fd8bef
Summary:
Level-based L0->L0 compaction operates on spans of files that aren't currently being compacted. It reduces the number of L0 files, thus making write stall conditions harder to reach.
- L0->L0 is triggered when base level is unavailable due to pending compactions
- L0->L0 always outputs one file of at most `max_level0_burst_file_size` bytes.
- Subcompactions are disabled for L0->L0 since we want to output one file.
- Input files are chosen as the longest span of available files that will fit within the size limit. This minimizes number of files in L0.
Closes https://github.com/facebook/rocksdb/pull/2027
Differential Revision: D4760318
Pulled By: ajkr
fbshipit-source-id: 9d07183
Summary:
It is confusing to have auto_roll_logger to stay under db/, which has nothing to do with database. Move filename together as it is a dependency.
Closes https://github.com/facebook/rocksdb/pull/2080
Differential Revision: D4821141
Pulled By: siying
fbshipit-source-id: ca7d768
Summary:
PinnableSlice
Summary:
Currently the point lookup values are copied to a string provided by the
user. This incures an extra memcpy cost. This patch allows doing point lookup
via a PinnableSlice which pins the source memory location (instead of
copying their content) and releases them after the content is consumed
by the user. The old API of Get(string) is translated to the new API
underneath.
Here is the summary for improvements:
value 100 byte: 1.8% regular, 1.2% merge values
value 1k byte: 11.5% regular, 7.5% merge values
value 10k byte: 26% regular, 29.9% merge values
The improvement for merge could be more if we extend this approach to
pin the merge output and delay the full merge operation until the user
actually needs it. We have put that for future work.
PS:
Sometimes we observe a small decrease in performance when switching from
t5452014 to this patch but with the old Get(string) API. The d
Closes https://github.com/facebook/rocksdb/pull/1756
Differential Revision: D4391738
Pulled By: maysamyabandeh
fbshipit-source-id: 6f3edd3
Summary:
…action
The two options, min_partial_merge_operands and verify_checksums_in_compaction, are not seldom used. Remove them to reduce the total number of options. Also remove them from Java and C interface.
Closes https://github.com/facebook/rocksdb/pull/1902
Differential Revision: D4601219
Pulled By: siying
fbshipit-source-id: aad4cb2
Summary:
reimplement the compaction expansion on lower level.
Considering such a case:
input level file: 1[B E] 2[F G] 3[H I] 4 [J M]
output level file: 5[A C] 6[D K] 7[L O]
If we initially pick file 2, now we will compact file 2 and 6. But we can safely compact 2, 3 and 6 without expanding the output level.
The previous code is messy and wrong.
In this diff, I first determine the input range [a, b], and output range [c, d],
then we get the range [e,f] = [min(a, c), max(b, d] and put all eligible clean-cut files within [e, f] into this compaction.
**Note: clean-cut means the files don't have the same user key on the boundaries of some files that are not chosen in this compaction**.
Closes https://github.com/facebook/rocksdb/pull/1760
Differential Revision: D4395564
Pulled By: lightmark
fbshipit-source-id: 2dc2c5c
Summary:
fix lite bugs
disable direct io in lite mode
Closes https://github.com/facebook/rocksdb/pull/1870
Differential Revision: D4559866
Pulled By: yiwu-arbug
fbshipit-source-id: 3761c51
Summary:
Remove disableDataSync, and another similarly named disable_data_sync options.
This is being done to simplify options, and also because the performance gains of this feature can be achieved by other methods.
Closes https://github.com/facebook/rocksdb/pull/1859
Differential Revision: D4541292
Pulled By: sagar0
fbshipit-source-id: 5b3a6ca
Summary:
merger.h was always a confusing name for me, simply give the file a better name
Closes https://github.com/facebook/rocksdb/pull/1836
Differential Revision: D4505357
Pulled By: IslamAbdelRahman
fbshipit-source-id: 07b28d8
Summary:
Currently the point lookup values are copied to a string provided by the user.
This incures an extra memcpy cost. This patch allows doing point lookup
via a PinnableSlice which pins the source memory location (instead of
copying their content) and releases them after the content is consumed
by the user. The old API of Get(string) is translated to the new API
underneath.
Here is the summary for improvements:
1. value 100 byte: 1.8% regular, 1.2% merge values
2. value 1k byte: 11.5% regular, 7.5% merge values
3. value 10k byte: 26% regular, 29.9% merge values
The improvement for merge could be more if we extend this approach to
pin the merge output and delay the full merge operation until the user
actually needs it. We have put that for future work.
PS:
Sometimes we observe a small decrease in performance when switching from
t5452014 to this patch but with the old Get(string) API. The difference
is a little and could be noise. More importantly it is safely
cancelled
Closes https://github.com/facebook/rocksdb/pull/1732
Differential Revision: D4374613
Pulled By: maysamyabandeh
fbshipit-source-id: a077f1a
Summary:
Previously we used TableCache::NewIterator() for multiple purposes (data
block iterator and range deletion iterator), and returned non-ok status in
the data block iterator. In one case where the caller only used the range
deletion block iterator (9e7cf3469b/db/version_set.cc (L965-L973)),
we didn't check/free the data block iterator containing non-ok status, which
caused a valgrind error.
So, this diff decouples creation of data block and range deletion block iterators,
and updates the callers accordingly. Both functions can return non-ok status
in an InternalIterator. Since the non-ok status is returned in an iterator that the
callers will definitely use, it should be more usable/less error-prone.
Closes https://github.com/facebook/rocksdb/pull/1513
Differential Revision: D4181423
Pulled By: ajkr
fbshipit-source-id: 835b8f5
Summary:
Note: reviewed in https://reviews.facebook.net/D65115
- DBIter maintains a range tombstone accumulator. We don't cleanup obsolete tombstones yet, so if the user seeks back and forth, the same tombstones would be added to the accumulator multiple times.
- DBImpl::NewInternalIterator() (used to make DBIter's underlying iterator) adds memtable/L0 range tombstones, L1+ range tombstones are added on-demand during NewSecondaryIterator() (see D62205)
- DBIter uses ShouldDelete() when advancing to check whether keys are covered by range tombstones
Closes https://github.com/facebook/rocksdb/pull/1464
Differential Revision: D4131753
Pulled By: ajkr
fbshipit-source-id: be86559
Summary:
During Get()/MultiGet(), build up a RangeDelAggregator with range
tombstones as we search through live memtable, immutable memtables, and
SST files. This aggregator is then used by memtable.cc's SaveValue() and
GetContext::SaveValue() to check whether keys are covered.
added tests for Get on memtables/files; end-to-end tests mainly in https://reviews.facebook.net/D64761
Closes https://github.com/facebook/rocksdb/pull/1456
Differential Revision: D4111271
Pulled By: ajkr
fbshipit-source-id: 6e388d4
Summary:
Changes in the diff
API changes:
- Introduce IngestExternalFile to replace AddFile (I think this make the API more clear)
- Introduce IngestExternalFileOptions (This struct will encapsulate the options for ingesting the external file)
- Deprecate AddFile() API
Logic changes:
- If our file overlap with the memtable we will flush the memtable
- We will find the first level in the LSM tree that our file key range overlap with the keys in it
- We will find the lowest level in the LSM tree above the the level we found in step 2 that our file can fit in and ingest our file in it
- We will assign a global sequence number to our new file
- Remove AddFile restrictions by using global sequence numbers
Other changes:
- Refactor all AddFile logic to be encapsulated in ExternalSstFileIngestionJob
Test Plan:
unit tests (still need to add more)
addfile_stress (https://reviews.facebook.net/D65037)
Reviewers: yiwu, andrewkr, lightmark, yhchiang, sdong
Reviewed By: sdong
Subscribers: jkedgar, hcz, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D65061
Summary:
This diff introduces RangeDelAggregator, which takes ownership of iterators
provided to it via AddTombstones(). The tombstones are organized in a two-level
map (snapshot stripe -> begin key -> tombstone). Tombstone creation avoids data
copy by holding Slices returned by the iterator, which remain valid thanks to pinning.
For compaction, we create a hierarchical range tombstone iterator with structure
matching the iterator over compaction input data. An aggregator based on that
iterator is used by CompactionIterator to determine which keys are covered by
range tombstones. In case of merge operand, the same aggregator is used by
MergeHelper. Upon finishing each file in the compaction, relevant range tombstones
are added to the output file's range tombstone metablock and file boundaries are
updated accordingly.
To check whether a key is covered by range tombstone, RangeDelAggregator::ShouldDelete()
considers tombstones in the key's snapshot stripe. When this function is used outside of
compaction, it also checks newer stripes, which can contain covering tombstones. Currently
the intra-stripe check involves a linear scan; however, in the future we plan to collapse ranges
within a stripe such that binary search can be used.
RangeDelAggregator::AddToBuilder() adds all range tombstones in the table's key-range
to a new table's range tombstone meta-block. Since range tombstones may fall in the gap
between files, we may need to extend some files' key-ranges. The strategy is (1) first file
extends as far left as possible and other files do not extend left, (2) all files extend right
until either the start of the next file or the end of the last range tombstone in the gap,
whichever comes first.
One other notable change is adding release/move semantics to ScopedArenaIterator
such that it can be used to transfer ownership of an arena-allocated iterator, similar to
how unique_ptr is used for malloc'd data.
Depends on D61473
Test Plan: compaction_iterator_test, mock_table, end-to-end tests in D63927
Reviewers: sdong, IslamAbdelRahman, wanning, yhchiang, lightmark
Reviewed By: lightmark
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D62205
Summary:
We always run consistency checks when compiling in debug mode
allow users to set Options::force_consistency_checks to true to be able to run such checks even when compiling in release mode
Test Plan:
make check -j64
make release
Reviewers: lightmark, sdong, yiwu
Reviewed By: yiwu
Subscribers: hermanlee4, andrewkr, yoshinorim, jkedgar, dhruba
Differential Revision: https://reviews.facebook.net/D64701
Summary:
Add new Iterator API, `SeekForPrev`: find the last key that <= target key
support prefix_extractor
support prefix_same_as_start
support upper_bound
not supported in iterators without Prev()
Also add tests in db_iter_test and db_iterator_test
Pass all tests
Cheers!
Test Plan: make all check -j64
Reviewers: andrewkr, yiwu, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D64149
Summary: Use ImmutableDBOptions/MutableDBOptions internally and DBOptions only for user-facing APIs. MutableDBOptions is barely a placeholder for now. I'll start to move options to MutableDBOptions in following diffs.
Test Plan:
make all check
Reviewers: yhchiang, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D64065
Summary:
* Change constructor of MutableCFOptions to depends only on ColumnFamilyOptions.
* Move `max_subcompactions`, `compaction_options_fifo` and `compaction_pri` to ImmutableCFOptions to make it clear that they are immutable.
Test Plan: existing unit tests.
Reviewers: yhchiang, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D63945
Summary: In T8216281 we decided to disable prefetching the index and filter during opening table handlers during startup (max_open_files = -1).
Test Plan: Rely on `IndexAndFilterBlocksOfNewTableAddedToCache` to guarantee L0 indexes and filters are still cached and change `PinL0IndexAndFilterBlocksTest` to make sure other levels are not cached (maybe add one more test to test we don't cache other levels?)
Reviewers: sdong, andrewkr
Reviewed By: andrewkr
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D59913
* Added new statistics and refactored to allow ioptions to be passed around as required to access environment and statistics pointers (and, as a convenient side effect, info_log pointer).
* Prevent incrementing compression counter when compression is turned off in options.
* Prevent incrementing compression counter when compression is turned off in options.
* Added two more supported compression types to test code in db_test.cc
* Prevent incrementing compression counter when compression is turned off in options.
* Added new StatsLevel that excludes compression timing.
* Fixed casting error in coding.h
* Fixed CompressionStatsTest for new StatsLevel.
* Removed unused variable that was breaking the Linux build
Summary: MyRocks release integration build breaks because we treat warnings caused by unused variables as errors. Variable `edit` is only used in debug builds. Therefore we need to guard it using `#ifndef NDEBUG` check.
Test Plan:
- `[p]arc diff --preview` for the default validation.
- Verify that release build fails before this fix and passes after applying it.
Reviewers: andrewkr, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D60423
Summary: Add option write_buffer_manager to help users control total memory spent on memtables across multiple DB instances.
Test Plan: Add a new unit test.
Reviewers: yhchiang, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: adela, benj, sumeet, muthu, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D59925
Summary:
We have alot of code duplication whenever we call FullMerge we keep duplicating the instrumentation and statistics code
This is a simple diff to refactor the code to use TimedFullMerge instead of FullMerge
Test Plan: COMPILE_WITH_ASAN=1 make check -j64
Reviewers: andrewkr, yhchiang, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D59577
Summary: Make CompactionOptionsFIFO a part of mutable_cf_options
Test Plan: UT
Reviewers: sdong
Reviewed By: sdong
Subscribers: andrewkr, lgalanis, dhruba
Differential Revision: https://reviews.facebook.net/D58653
Summary:
GetObsoleteFiles() and LogAndApply() functions modify obsolete_manifests_ vector
we need to make sure that the mutex is held when we modify the obsolete_manifests_
Test Plan: run the test under TSAN
Reviewers: andrewkr
Reviewed By: andrewkr
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D58011
Summary: Currently we estimate bytes needed for compaction by assuming fanout value to be level multiplier. It overestimates when size of a level exceeds the target by large. We estimate by the ratio of actual sizes in levels instead.
Test Plan: Fix existing test cases and add a new one.
Reviewers: IslamAbdelRahman, igor, yhchiang
Reviewed By: yhchiang
Subscribers: MarkCallaghan, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D57789
Summary:
This is needed so we can measure compression ratio improvements
achieved by D52287.
The property compares raw data size against the total file size for a given
level. If the level is empty it should return 0.0.
Test Plan: new unit test
Reviewers: IslamAbdelRahman, yhchiang, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D56967
Summary: We use object `v` in the error message, which is not initialized if the edit is column family manipulation. This doesn't provide much useful info, so this diff is removing it. Instead, it dumps actual VersionEdit contents.
Test Plan: compiles. would be great to get tests in version_set_test.cc that cover cases where a file write fails
Reviewers: sdong, yhchiang, andrewkr
Reviewed By: andrewkr
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D56349
Summary:
There is a hardcoded constraint in our statistics collection that prevents reading properties from more than 20 SST files. This means our statistics will be very inaccurate for databases with > 20 files since additional files are just ignored. The purpose of constraining the number of files used is to bound the I/O performed during statistics collection, since these statistics need to be recomputed every time the database reopened.
However, this constraint doesn't take into account the case where option "max_open_files" is -1. In that case, all the file metadata has already been read, so MaybeInitializeFileMetaData() won't incur any I/O cost. so this diff gets rid of the 20-file constraint in case max_open_files == -1.
Test Plan:
write into unit test db/db_properties_test.cc - "ValidateSampleNumber".
We generate 20 files with 2 rows and 10 files with 1 row.
If max_open_files !=-1, the `rocksdb.estimate-num-keys` should be (10*1 + 10*2)/20 * 30 = 45. Otherwise, it should be the ground truth, 50.
{F1089153}
Reviewers: andrewkr
Reviewed By: andrewkr
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D56253
Summary:
When a block based table file is opened, if prefetch_index_and_filter is true, it will prefetch the index and filter blocks, putting them into the block cache.
What this feature adds: when a L0 block based table file is opened, if pin_l0_filter_and_index_blocks_in_cache is true in the options (and prefetch_index_and_filter is true), then the filter and index blocks aren't released back to the block cache at the end of BlockBasedTableReader::Open(). Instead the table reader takes ownership of them, hence pinning them, ie. the LRU cache will never push them out. Meanwhile in the table reader, further accesses will not hit the block cache, thus avoiding lock contention.
Test Plan:
'export TEST_TMPDIR=/dev/shm/ && DISABLE_JEMALLOC=1 OPT=-g make all valgrind_check -j32' is OK.
I didn't run the Java tests, I don't have Java set up on my devserver.
Reviewers: sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D56133
Summary: We were not measuring the time spent in merge_operator when called from Version::Get()
Test Plan: added a unittest
Reviewers: sdong, yhchiang
Reviewed By: yhchiang
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D55905
Summary:
When subcompaction is used, all subcompactions share the same Compaction
pointer in CompactionJob while each subcompaction all keeps their mutable
stats in SubcompactionState. However, there're still some mutable part
that is currently store in the shared Compaction pointer.
This patch makes two changes:
1. Make the shared Compaction pointer const so that it can never be modified
during the compaction.
2. Move necessary states from Compaction to SubcompactionState.
3. Make functions of Compaction const if the function does not modify
its internal state.
Test Plan: rocksdb and MyRocks test
Reviewers: sdong, kradhakrishnan, andrewkr, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: andrewkr, dhruba, yoshinorim, gunnarku, leveldb
Differential Revision: https://reviews.facebook.net/D55923
Summary:
When a block based table file is opened, if prefetch_index_and_filter is true, it will prefetch the index and filter blocks, putting them into the block cache.
What this feature adds: when a L0 block based table file is opened, if pin_l0_filter_and_index_blocks_in_cache is true in the options (and prefetch_index_and_filter is true), then the filter and index blocks aren't released back to the block cache at the end of BlockBasedTableReader::Open(). Instead the table reader takes ownership of them, hence pinning them, ie. the LRU cache will never push them out. Meanwhile in the table reader, further accesses will not hit the block cache, thus avoiding lock contention.
When the table reader is destroyed, it releases the pinned blocks (if there were any). This has to happen before the cache is destroyed, so I had to introduce a TableReader::Close(), to guarantee the order of destruction.
Test Plan:
Added two unit tests for this. Existing unit tests run fine (default is pin_l0_filter_and_index_blocks_in_cache=false).
DISABLE_JEMALLOC=1 OPT=-g make all valgrind_check -j32
Mac: OK.
Linux: with D55287 patched in it's OK.
Reviewers: sdong
Reviewed By: sdong
Subscribers: andrewkr, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D54801
Summary:
- Keep track of obsolete manifests in VersionSet
- Updated FindObsoleteFiles() to put obsolete manifests in the JobContext for later use by PurgeObsoleteFiles()
- Added test case that verifies a stale manifest is deleted by a non-full purge
Test Plan:
$ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation
Reviewers: IslamAbdelRahman, yoshinorim, sdong
Reviewed By: sdong
Subscribers: andrewkr, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D55269
Summary:
Fixed two related race conditions in backup creation.
(1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files
from being deleted while it is copying; however, the MANIFEST file could still
rotate during this time. The fix is to stop deleting the old manifest in the
rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs
(can only happen when file deletions are enabled).
(2) CreateNewBackup() did not account for the CURRENT file being mutable.
This is significant because the files returned by GetLiveFiles() contain a
particular manifest filename, but the manifest to which CURRENT refers can
change at any time. This causes problems when CURRENT changes between the call
to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I
manually forge a CURRENT file referring to the manifest filename returned in
GetLiveFiles().
(2) also applies to the checkpointing code, so let me know if this approach is
good and I'll make the same change there.
Test Plan:
new test for roll manifest during backup creation.
running the test before this change:
$ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation
...
IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory
running the test after this change:
$ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation
...
[ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation
[ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms)
Reviewers: IslamAbdelRahman, anthony, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D54711
Summary:
Add a new compaction priority as following:
For every file, we calculate total size of files overalapping with the file in the next level, over the file's size itself. The file with smallest ratio will be picked first.
My "db_bench --fillrandom" shows about 5% less compaction than kOldestSmallestSeqFirst if --hard_pending_compaction_bytes_limit value to keep LSM tree in shape. If not limiting hard_pending_compaction_bytes_limit, improvement is only 1% or 2%.
Test Plan: Add a unit test
Reviewers: andrewkr, kradhakrishnan, anthony, IslamAbdelRahman, yhchiang
Reviewed By: yhchiang
Subscribers: MarkCallaghan, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D54075
Summary:
Following up on D53493, we can still enable the filter-skipping
optimization for last file in L0. It's correct to assume the key will be present
in the last L0 file when we're hit-optimized and L0 is deepest.
The FilePicker encapsulates the state for traversing each level's files, so I
needed to make it expose whether the returned file is last in its level.
Test Plan:
verified below test fails before this patch and passes afterwards.
The change to how the test memtable is populated is needed so file 1 has keys
(0, 30, 60), file 2 has keys (10, 40, 70), etc.
$ ./db_universal_compaction_test --gtest_filter=UniversalCompactionNumLevels/DBTestUniversalCompaction.OptimizeFiltersForHits/*
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D53583
Summary: It's a regression bug caused by e089db40f9. With the change, if options.optimize_filters_for_hits=true and there are only L0 files (like single level universal compaction), we skip all the files in L0, which is more than necessary. Fix it by always trying to query bloom filter for files in level 0.
Test Plan: Add a unit test for it.
Reviewers: anthony, rven, yhchiang, IslamAbdelRahman, kradhakrishnan, andrewkr
Reviewed By: andrewkr
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D53493
Summary: Revert the functionaility of D7809 (but I'm keeping the logging and test code). We decided it was dangerous to ignore sync failures based on attempting to read the data written. The read does not tell us whether the data was synced.
Test Plan: There was no test for the particular functionaility that was reverted. Keeping the test code from D7809 that tests whether we set the DB to be readonly when paranoid checks are enabled.
Reviewers: rven, yhchiang, kradhakrishnan, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D52989
Summary: That line used to dereference `column_family_data`, which is nullptr if we're creating a column family.
Test Plan: `make -j check`
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D52881
Summary: It's usually hard for users to set a value of options.delayed_write_rate. With this diff, after slowdown condition triggers, we greedily reduce write rate if estimated pending compaction bytes increase. If estimated compaction pending bytes drop, we increase the write rate.
Test Plan:
Add a unit test
Test with db_bench setting:
TEST_TMPDIR=/dev/shm/ ./db_bench --benchmarks=fillrandom -num=10000000 --soft_pending_compaction_bytes_limit=1000000000 --hard_pending_compaction_bytes_limit=3000000000 --delayed_write_rate=100000000
and make sure without the commit, write stop will happen, but with the commit, it will not happen.
Reviewers: igor, anthony, rven, yhchiang, kradhakrishnan, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D52131
Summary:
When Get() or NewIterator() trigger file loads, skip caching the filter block if
(1) optimize_filters_for_hits is set and (2) the file is on the bottommost
level. Also skip checking filters under the same conditions, which means that
for a preloaded file or a file that was trivially-moved to the bottom level, its
filter block will eventually expire from the cache.
- added parameters/instance variables in various places in order to propagate the config ("skip_filters") from version_set to block_based_table_reader
- in BlockBasedTable::Rep, this optimization prevents filter from being loaded when the file is opened simply by setting filter_policy = nullptr
- in BlockBasedTable::Get/BlockBasedTable::NewIterator, this optimization prevents filter from being used (even if it was loaded already) by setting filter = nullptr
Test Plan:
updated unit test:
$ ./db_test --gtest_filter=DBTest.OptimizeFiltersForHits
will also run 'make check'
Reviewers: sdong, igor, paultuckfield, anthony, rven, kradhakrishnan, IslamAbdelRahman, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D51633
Summary:
List of changes:
1) Fix the snprintf() usage in cases where wrong variable was used to determine the output buffer size.
2) Remove unnecessary checks before calling delete operator.
3) Increase code correctness by using size_t type when getting vector's size.
4) Unify the coding style by removing namespace::std usage at the top of the file to confirm to the majority usage.
5) Fix various lint errors pointed out by 'arc lint'.
Test Plan:
Code review and build:
git diff
make clean
make -j 32 commit-prereq
arc lint
Reviewers: kradhakrishnan, sdong, rven, anthony, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D51849
Summary:
Currently, transactions can fail even if there is no actual write conflict. This is due to relying on only the memtables to check for write-conflicts. Users have to tune memtable settings to try to avoid this, but it's hard to figure out exactly how to tune these settings.
With this diff, TransactionDB will use both memtables and SST files to determine if there are any write conflicts. This relies on the fact that BlockBasedTable stores sequence numbers for all writes that happen after any open snapshot. Also, D50295 is needed to prevent SingleDelete from disappearing writes (the TODOs in this test code will be fixed once the other diff is approved and merged).
Note that Optimistic transactions will still rely on tuning memtable settings as we do not want to read from SST while on the write thread. Also, memtable settings can still be used to reduce how often TransactionDB needs to read SST files.
Test Plan: unit tests, db bench
Reviewers: rven, yhchiang, kradhakrishnan, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb, yoshinorim
Differential Revision: https://reviews.facebook.net/D50475
Summary: Deprecate options.soft_rate_limit, which is hard to tune, with options.soft_pending_compaction_bytes_limit, which would trigger the slowdown if estimated pending compaction bytes exceeds the threshold. The hope is to make it more striaght-forward to tune.
Test Plan: Modify DBTest.SoftLimit to cover options.soft_pending_compaction_bytes_limit instead; run all unit tests.
Reviewers: IslamAbdelRahman, yhchiang, rven, kradhakrishnan, igor, anthony
Reviewed By: anthony
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D51117
Summary: Introduce a compaction picking priority that picks files who contains the oldest rows to compact. This is a mode that slightly improves write amplification for random update cases.
Test Plan: Add a unit test and run it in valgrind too.
Reviewers: yhchiang, anthony, IslamAbdelRahman, rven, kradhakrishnan, MarkCallaghan, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D51459
Summary: crash_test sometimes fails, hitting the add file overlapping assert. Add information in info logs help us to find the bug.
Test Plan: Run all test suites. Do some manual tests to make sure printing is correct.
Reviewers: kradhakrishnan, yhchiang, anthony, IslamAbdelRahman, rven, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D49017
Summary: We don't yet have a CI build for iOS, so our iOS compile gets broken sometimes. Most of the errors are from assumption that size_t is 64-bit, while it's actually 32-bit on some (all?) iOS platforms. This diff fixes the compile.
Test Plan:
TARGET_OS=IOS make static_lib
Observe there are no warnings
Reviewers: sdong, anthony, IslamAbdelRahman, kradhakrishnan, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D49029
Summary: As above.
Test Plan: USE_CLANG=1 make check -j
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48981
We will need the log number to validate the recycle-style CRCs. The log
is helpful for debugging, but optional, as not all callers have it.
Signed-off-by: Sage Weil <sage@redhat.com>
When we recycle log files, we need to mix the log number into the CRC
for each record. Note that for logs that don't get recycled (like the
manifest), we always pass a log_number of 0 and false.
Signed-off-by: Sage Weil <sage@redhat.com>
Summary: In MyRocks, it is sometimes important to get propeties only for the subset of the database. This diff implements the API in RocksDB.
Test Plan: ran the GetPropertiesOfTablesInRange
Reviewers: rven, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48651
Summary:
Add kill points in:
1. after creating a file
2. before writing a manifest record
3. before syncing manifest
4. before creating a new current file
5. after creating a new current file
Test Plan: Run all current tests.
Reviewers: yhchiang, igor, anthony, IslamAbdelRahman, rven, kradhakrishnan
Reviewed By: kradhakrishnan
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D48855
Summary:
Separate a new class InternalIterator from class Iterator, when the look-up is done internally, which also means they operate on key with sequence ID and type.
This change will enable potential future optimizations but for now InternalIterator's functions are still the same as Iterator's.
At the same time, separate the cleanup function to a separate class and let both of InternalIterator and Iterator inherit from it.
Test Plan: Run all existing tests.
Reviewers: igor, yhchiang, anthony, kradhakrishnan, IslamAbdelRahman, rven
Reviewed By: rven
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D48549
Summary:
Add options.compaction_pri, which specifies the policy about which file to compact first.
kCompactionPriByLargestSeq will compact oldest files first.
Verified the behavior in db_bench but did not write unit tests yet. Also need to make it settable through option string and dynamically changeable.
Test Plan: Will write unit tests
Reviewers: igor, rven, anthony, kradhakrishnan, IslamAbdelRahman, yhchiang, MarkCallaghan
Reviewed By: yhchiang
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D45951
Summary:
This patch finally fixes the ColumnFamilyTest.ReadDroppedColumnFamily test. The test has been failing very sporadically and it was hard to repro. However, I managed to write a new tests that reproes the failure deterministically.
Here's what happens:
1. We start the flush for the column family
2. We check if the column family was dropped here: a3fc49bfdd/db/flush_job.cc (L149)
3. This check goes through, ends up in InstallMemtableFlushResults() and it goes into LogAndApply()
4. At about this time, we start dropping the column family. Dropping the column family process gets to LogAndApply() at about the same time as LogAndApply() from flush process
5. Drop column family goes through LogAndApply() first, marking the column family as dropped.
6. Flush process gets woken up and gets a chance to write to the MANIFEST. However, this is where it gets stuck: a3fc49bfdd/db/version_set.cc (L1975)
7. We see that the column family was dropped, so there is no need to write to the MANIFEST. We return OK.
8. Flush gets OK back from LogAndApply() and it deletes the memtable, thinking that the data is now safely persisted to sst file.
The fix is pretty simple. Instead of OK, we return ShutdownInProgress. This is not really true, but we have been using this status code to also mean "this operation was canceled because the column family has been dropped".
The fix is only one LOC. All other code is related to tests. I added a new test that reproes the failure. I also moved SleepingBackgroundTask to util/testutil.h (because I needed it in column_family_test for my new test). There's plenty of other places where we reimplement SleepingBackgroundTask, but I'll address that in a separate commit.
Test Plan:
1. new test
2. make check
3. Make sure the ColumnFamilyTest.ReadDroppedColumnFamily doesn't fail on Travis: https://travis-ci.org/facebook/rocksdb/jobs/79952386
Reviewers: yhchiang, anthony, IslamAbdelRahman, kradhakrishnan, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D46773
Summary:
Up to this point, the subcompactions that make up a compaction
job have been divided based on the key range of the L1 files, and each
subcompaction has handled the key range of only one file. However
DBOption.max_subcompactions allows the user to designate how many
subcompactions at most to perform. This patch updates the
CompactionJob::GetSubcompactionBoundaries() to determine these
divisions accordingly based on that option and other input/system factors.
The current approach orders the starting and/or ending keys of certain
compaction input files and then generates a histogram to approximate the
size covered by the key range between each consecutive pair of keys. Then
it groups these ranges into groups so that the sizes are approximately equal
to one another. The approach has also been adapted to work for universal
compaction as well instead of just for level-based compaction as it was before.
These subcompactions are then executed in parallel by locally spawning
threads, one for each. The results are then aggregated and the compaction
completed.
Test Plan: make all && make check
Reviewers: yhchiang, anthony, igor, noetzli, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D43269
Summary:
In some cases, equality comparisons can be done more efficiently than three-way
comparisons. There are quite a few places in the code where we only care about
equality. This patch adds an Equal() method that defaults to using the
Compare() method.
Test Plan: make clean all check
Reviewers: rven, anthony, yhchiang, igor, sdong
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D46233
Summary: TableCache::Get() puts parameters in the wrong places so that table readers created by Get() will not have the histogram updated.
Test Plan: Will write a unit test for that.
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D46035
Summary:
This patch adds "rocksdb.aggregated-table-properties"
and "rocksdb.aggregated-table-properties-at-levelN", the former
returns the aggreated table properties of a column family,
while the later returns the aggregated table properties
of the specified level N.
Test Plan: Added tests in db_test
Reviewers: igor, sdong, IslamAbdelRahman, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D45087
Summary:
Add a counter of estimated bytes the DB needs to compact for all the compactions to finish. Expose it as a DB Property.
In the future, we can use threshold of this counter to replace soft rate limit and hard rate limit. A single threshold of estimated compaction debt in bytes will be easier for users to reason about when should slow down and stopping than more abstract soft and hard rate limits.
Test Plan: Add unit tests
Reviewers: IslamAbdelRahman, yhchiang, rven, kradhakrishnan, anthony, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D44205
Summary: Add a new DB property that calculate the total size of files used by all RocksDB Versions
Test Plan: Unittests for the new property
Reviewers: igor, yhchiang, anthony, rven, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D44799
Summary: In internal stats, remember read latency histogram, if statistics is enabled. It can be retrieved from DB::GetProperty() with "rocksdb.dbstats" property, if it is enabled.
Test Plan: Manually run db_bench and prints out "rocksdb.dbstats" by hand and make sure it prints out as expected
Reviewers: igor, IslamAbdelRahman, rven, kradhakrishnan, anthony, yhchiang
Reviewed By: yhchiang
Subscribers: MarkCallaghan, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D44193
Summary: Add a new option that all LoadTableHandlers to use multiple threads to load files on DB Open and Recover
Test Plan:
make check -j64
COMPILE_WITH_TSAN=1 make check -j64
DISABLE_JEMALLOC=1 make all valgrind_check -j64 (still running)
Reviewers: yhchiang, anthony, rven, kradhakrishnan, igor, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D43755
Summary:
Changed compaction_job_test to support better/more thorough
tests and added two tests. Also changed MockFileContents
to order using InternalKeyComparator.
Test Plan: make compaction_job_test && ./compaction_job_test; make all && make check
Reviewers: sdong, rven, igor, yhchiang, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42837
Summary:
UpdateAccumulatedStats() is used to optimize compaction decision
esp. when the number of deletion entries are high, but this function
can slowdown DBOpen esp. in disk environment.
This patch adds DBOptions::skip_sats_update_on_db_open, which skips
UpdateAccumulatedStats() in DB::Open() time when it's set to true.
Test Plan: Add DBCompactionTest.SkipStatsUpdateTest
Reviewers: igor, anthony, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: tnovak, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42843
Summary:
As of now compactions involving files from Level 0 and Level 1 are single
threaded because the files in L0, although sorted, are not range partitioned like
the other levels. This means that during L0-L1 compaction each file from L1
needs to be merged with potentially all the files from L0.
This attempt to parallelize the L0-L1 compaction assigns a thread and a
corresponding iterator to each L1 file that then considers only the key range
found in that L1 file and only the L0 files that have those keys (and only the
specific portion of those L0 files in which those keys are found). In this way
the overlap is minimized and potentially eliminated between different iterators
focusing on the same files.
The first step is to restructure the compaction logic to break L0-L1 compactions
into multiple, smaller, sequential compactions. Eventually each of these smaller
jobs will be run simultaneously. Areas to pay extra attention to are
# Correct aggregation of compaction job statistics across multiple threads
# Proper opening/closing of output files (make sure each thread's is unique)
# Keys that span multiple L1 files
# Skewed distributions of keys within L0 files
Test Plan: Make and run db_test (newer version has separate compaction tests) and compaction_job_stats_test
Reviewers: igor, noetzli, anthony, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42699
Summary:
Fixes T6548822. Added a new function for estimating the size of the live data
as proposed in the task. The value can be accessed through the property
rocksdb.estimate-live-data-size.
Test Plan:
There are two unit tests in version_set_test and a simple test in db_test.
make version_set_test && ./version_set_test;
make db_test && ./db_test gtest_filter=GetProperty
Reviewers: rven, igor, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D41493
Summary: We want to keep Env a think layer for better portability. Less platform dependent codes should be moved out of Env. In this patch, I create a wrapper of file readers and writers, and put rate limiting, write buffering, as well as most perf context instrumentation and random kill out of Env. It will make it easier to maintain multiple Env in the future.
Test Plan: Run all existing unit tests.
Reviewers: anthony, kradhakrishnan, IslamAbdelRahman, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D42321
Summary:
When we first started, max_background_flushes was 0 by default and compaction thread was executing flushes (since there was no flush thread). Then, we switched the default max_background_flushes to 1. However, we still support the case where there is no flush thread and flushes are done in compaction. This is making our code a bit more complicated. By not supporting this use-case we can make our code simpler.
We have a special case that when you set max_background_flushes to 0, we
schedule the flush to execute on the compaction thread.
Test Plan: make check (there might be some unit tests that depend on this behavior)
Reviewers: IslamAbdelRahman, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D41931
Summary: Try to allocate LevelFileIteratorState and LevelFileNumIterator from DB iterator's arena, instead of calling malloc and free.
Test Plan: valgrind check
Reviewers: rven, yhchiang, anthony, kradhakrishnan, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D40929
Summary:
We slow down data into the database to the rate of options.delayed_write_rate (a new option) with this patch.
The thread synchronization approach I take is to still synchronize write controller by DB mutex and GetDelay() is inside DB mutex. Try to minimize the frequency of getting time in GetDelay(). I verified it through db_bench and it seems to work
hard_rate_limit is deprecated.
options.delayed_write_rate is still not dynamically changeable. Need to work on it as a follow-up.
Test Plan: Add new unit tests in db_test
Reviewers: yhchiang, rven, kradhakrishnan, anthony, MarkCallaghan, igor
Reviewed By: igor
Subscribers: ikabiljo, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D36351
Andrew Kryczka