Commit graph

120 commits

Author SHA1 Message Date
Igor Canadi eb12e47e0e Killing Transform Rep
Summary:
Let's get rid of TransformRep and it's children. We have confirmed that HashSkipListRep works better with multifeed, so there is no benefit to keeping this around.

This diff is mostly just deleting references to obsoleted functions. I also have a diff for fbcode that we'll need to push when we switch to new release.

I had to expose HashSkipListRepFactory in the client header files because db_impl.cc needs access to GetTransform() function for SanitizeOptions.

Test Plan: make check

Reviewers: dhruba, haobo, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14397
2013-12-03 12:42:15 -08:00
Igor Canadi 469a9f32a7 Fix two nasty use-after-free-bugs
Summary:
These bugs were caught by ASAN crash test.
1. The first one, in table/filter_block.cc is very nasty. We first reference entries_ and store the reference to Slice prev. Then, we call entries_.append(), which can change the reference. The Slice prev now points to junk.
2. The second one is a bug in a test, so it's not very serious. Once we set read_opts.prefix, we never clear it, so some other function might still reference it.

Test Plan: asan crash test now runs more than 5 mins. Before, it failed immediately. I will run the full one, but the full one takes quite some time (5 hours)

Reviewers: dhruba, haobo, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14223
2013-11-19 21:01:48 -08:00
kailiu 97d8e573a6 make util/env_posix.cc work under mac
Summary: This diff invoves some more complicated issues in the posix environment.

Test Plan: works under mac os. will need to verify dev box.

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14061
2013-11-16 23:44:39 -08:00
Pascal Borreli 443e04e62d Fixed typos 2013-11-16 11:21:34 +00:00
Kai Liu 88ba331c1a Add the index/filter block cache
Summary: This diff leverage the existing block cache and extend it to cache index/filter block.

Test Plan:
Added new tests in db_test and table_test

The correctness is checked by:

1. make check
2. make valgrind_check

Performance is test by:

1. 10 times of build_tools/regression_build_test.sh on two versions of rocksdb before/after the code change. Test results suggests no significant difference between them. For the two key operatons `overwrite` and `readrandom`, the average iops are both 20k and ~260k, with very small variance).
2. db_stress.

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, haobo, xjin

Differential Revision: https://reviews.facebook.net/D13167
2013-11-12 22:46:51 -08:00
Kai Liu 22e1b04deb Quick fix for a string format
Summary:

Fix one more string format issue that throws warning in mac
2013-11-12 21:22:32 -08:00
shamdor c2be2cba04 WAL log retention policy based on archive size.
Summary:
Archive cleaning will still happen every WAL_ttl seconds
but archived logs will be deleted only if archive size
is greater then a WAL_size_limit value.
Empty archived logs will be deleted evety WAL_ttl.

Test Plan:
1. Unit tests pass.
2. Benchmark.

Reviewers: emayanke, dhruba, haobo, sdong, kailiu, igor

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13869
2013-11-06 18:46:28 -08:00
Dhruba Borthakur b4ad5e89ae Implement a compressed block cache.
Summary:
Rocksdb can now support a uncompressed block cache, or a compressed
block cache or both. Lookups first look for a block in the
uncompressed cache, if it is not found only then it is looked up
in the compressed cache. If it is found in the compressed cache,
then it is uncompressed and inserted into the uncompressed cache.

It is possible that the same block resides in the compressed cache
as well as the uncompressed cache at the same time. Both caches
have their own individual LRU policy.

Test Plan: Unit test case attached.

Reviewers: kailiu, sdong, haobo, leveldb

Reviewed By: haobo

CC: xjin, haobo

Differential Revision: https://reviews.facebook.net/D12675
2013-11-01 14:31:35 -07:00
Piyush Garg 1e4375d2ef Task #3071144 Enhance ldb (db dump tool for leveldb) to report row counters for each row type
Summary: Added an option --count_delim=<char> which takes the given character as delimiter ('.' by default) and reports count of each row type found in the db

Test Plan:
1. Created test in file (for DBDumperCommand) rocksdb/tools/ldb_test.py which puts various key value pair in db and checks the output using dump --count_delim ,--count_delim="." and --count_delim=",".
2. Created test in file (for InternalDumperCommand) rocksdb/tools/ldb_test.py which puts various key value pair in db and checks the output using dump --count_delim ,--count_delim="." and --count_delim=",".
3. Manually created a database with several keys of several type and verified by running the command
   ./ldb db=<path> dump --count_delim="<char>"
   ./ldb db=<path> idump --count_delim="<char>"

Reviewers: vamsi, dhruba, emayanke, kailiu

Reviewed By: vamsi

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13815
2013-11-01 13:59:14 -07:00
Igor Canadi 138a8eee8e Fix make release
Summary: Don't define if already defined.

Test Plan: Running make release in parallel, will not commit if it fails.

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13833
2013-10-31 11:47:22 -07:00
Siying Dong f03b2df010 Follow-up Cleaning-up After D13521
Summary:
This patch is to address @haobo's comments on D13521:
1. rename Table to be TableReader and make its factory function to be GetTableReader
2. move the compression type selection logic out of TableBuilder but to compaction logic
3. more accurate comments
4. Move stat name constants into BlockBasedTable implementation.
5. remove some uncleaned codes in simple_table_db_test

Test Plan: pass test suites.

Reviewers: haobo, dhruba, kailiu

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13785
2013-10-30 10:52:33 -07:00
Siying Dong d4eec30ed0 Make "Table" pluggable
Summary: This patch makes Table and TableBuilder a abstract class and make all the implementation of the current table into BlockedBasedTable and BlockedBasedTable Builder.

Test Plan: Make db_test.cc to work with block based table. Add a new test simple_table_db_test.cc where a different simple table format is implemented.

Reviewers: dhruba, haobo, kailiu, emayanke, vamsi

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13521
2013-10-28 17:54:09 -07:00
Igor Canadi 8ace6b0f91 Run benchmark with no debug
Summary: assert(Overlap) significantly slows down the benchmark. Ignore assertions when executing blob_store_bench.

Test Plan: Ran the benchmark

Reviewers: dhruba, haobo, kailiu

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13737
2013-10-28 17:42:33 -07:00
Igor Canadi 17991cd5a0 Fix data race in BlobStore benchmark
Summary: Apparently C++ doesn't like it if you copy around its atomic<> variables. When running a benchmark for a longer time, benchmark used to stall. Changed WorkerThread in config to WorkerThread*. It works now.

Test Plan: Ran benchmark

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13731
2013-10-28 16:31:44 -07:00
Slobodan Predolac e44976b199 Conversion of db_bench, db_stress and db_repl_stress to use gflags
Summary: Converted db_stress, db_repl_stress and db_bench to use gflags

Test Plan: I tested by printing out all the flags from old and new versions. Tried defaults, + various combinations with "interesting flags". Also, tested by running db_crashtest.py and db_crashtest2.py.

Reviewers: emayanke, dhruba, haobo, kailiu, sdong

Reviewed By: emayanke

CC: leveldb, xjin

Differential Revision: https://reviews.facebook.net/D13581
2013-10-24 07:43:14 -07:00
Igor Canadi 7e2c1ba173 BlobStore Benchmark
Summary:
Finally, arc diff works again! This has been sitting in my repo for a while.

I would like some comments on my BlobStore benchmark. We don't have to check this in.

Also, I don't do any fsync in the BlobStore, so this is all extremely fast. I'm not sure what durability guarantees we need from the BlobStore.

Test Plan: Nope

Reviewers: dhruba, haobo, kailiu, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13527
2013-10-23 17:31:12 -07:00
Dhruba Borthakur 9cd221094c Add appropriate LICENSE and Copyright message.
Summary:
Add appropriate LICENSE and Copyright message.

Test Plan:
make check

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-10-16 17:48:41 -07:00
Siying Dong 88f2f89068 Change Function names from Compaction->Flush When they really mean Flush
Summary: When I debug the unit test failures when enabling background flush thread, I feel the function names can be made clearer for people to understand. Also, if the names are fixed, in many places, some tests' bugs are obvious (and some of those tests are failing). This patch is to clean it up for future maintenance.

Test Plan: Run test suites.

Reviewers: haobo, dhruba, xjin

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13431
2013-10-14 15:12:15 -07:00
Dhruba Borthakur 4463b11cad Migrate names of properties from 'leveldb' prefix to 'rocksdb' prefix.
Summary: Migrate names of properties from 'leveldb' prefix to 'rocksdb' prefix.

Test Plan: make check

Reviewers: emayanke, haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13311
2013-10-06 00:14:26 -07:00
Dhruba Borthakur a143ef9b38 Change namespace from leveldb to rocksdb
Summary:
Change namespace from leveldb to rocksdb. This allows a single
application to link in open-source leveldb code as well as
rocksdb code into the same process.

Test Plan: compile rocksdb

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13287
2013-10-04 11:59:26 -07:00
Mayank Agarwal 6b34021fc2 Triggering verify for gets also
Summary: Will use iterators to verify keys in the db for half of its keys and Gets for the other half.

Test Plan: ./db_stress --max_key=1000 --ops_per_thread=100

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13227
2013-10-02 11:22:17 -07:00
Natalie Hildebrandt 7edb92b843 Phase 2 of iterator stress test
Summary: Using an iterator instead of the Get method, each thread goes through a portion of the database and verifies values by comparing to the shared state.

Test Plan:
./db_stress --db=/tmp/tmppp --max_key=10000 --ops_per_thread=10000

To test some basic cases, the following lines can be added (each set in turn) to the verifyDb method with the following expected results:

    // Should abort with "Unexpected value found"
    shared.Delete(start);

    // Should abort with "Value not found"
    WriteOptions write_opts;
    db_->Delete(write_opts, Key(start));

    // Should succeed
    WriteOptions write_opts;
    shared.Delete(start);
     db_->Delete(write_opts, Key(start));

    // Should abort with "Value not found"
    WriteOptions write_opts;
    db_->Delete(write_opts, Key(start + (end-start)/2));

    // Should abort with "Value not found"
    db_->Delete(write_opts, Key(end-1));

    // Should abort with "Unexpected value"
    shared.Delete(end-1);

    // Should abort with "Unexpected value"
    shared.Delete(start + (end-start)/2);

    // Should abort with "Value not found"
    db_->Delete(write_opts, Key(start));
    shared.Delete(start);
    db_->Delete(write_opts, Key(end-1));
    db_->Delete(write_opts, Key(end-2));

To test the out of range abort, change the key in the for loop to Key(i+1), so that the key defined by the index i is now outside of the supposed range of the database.

Reviewers: emayanke

Reviewed By: emayanke

CC: dhruba, xjin

Differential Revision: https://reviews.facebook.net/D13071
2013-09-30 16:48:00 -07:00
Natalie Hildebrandt 9262061b0d Fixing crashing tests to include iterpercent param
Summary: Adding in the iterpercent flag to tests.

Test Plan: make crash_test

Reviewers: emayanke

Reviewed By: emayanke

Differential Revision: https://reviews.facebook.net/D13035
2013-09-20 16:27:22 -07:00
Natalie Hildebrandt 433541823c Phase 1 of an iterator stress test
Summary:
Added MultiIterate() which does a seek and some Next/Prev
calls.  Iterator status is checked only, no data integrity check

Test Plan:
make db_stress
./db_stress --iterpercent=<nonzero value> --readpercent=, etc.

Reviewers: emayanke, dhruba, xjin

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12915
2013-09-19 16:47:24 -07:00
Dhruba Borthakur 4012ca1c7b Added a parameter to limit the maximum space amplification for universal compaction.
Summary:
Added a new field called max_size_amplification_ratio in the
CompactionOptionsUniversal structure. This determines the maximum
percentage overhead of space amplification.

The size amplification is defined to be the ratio between the size of
the oldest file to the sum of the sizes of all other files. If the
size amplification exceeds the specified value, then min_merge_width
and max_merge_width are ignored and a full compaction of all files is done.
A value of 10 means that the size a database that stores 100 bytes
of user data could occupy 110 bytes of physical storage.

Test Plan: Unit test DBTest.UniversalCompactionSpaceAmplification added.

Reviewers: haobo, emayanke, xjin

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12825
2013-09-13 16:27:18 -07:00
Dhruba Borthakur 1186192ed1 Replace include/leveldb with include/rocksdb.
Summary: Replace include/leveldb with include/rocksdb.

Test Plan:
make clean; make check
make clean; make release

Differential Revision: https://reviews.facebook.net/D12489
2013-08-23 10:51:00 -07:00
Jim Paton 74781a0c49 Add three new MemTableRep's
Summary:
This patch adds three new MemTableRep's: UnsortedRep, PrefixHashRep, and VectorRep.

UnsortedRep stores keys in an std::unordered_map of std::sets. When an iterator is requested, it dumps the keys into an std::set and iterates over that.

VectorRep stores keys in an std::vector. When an iterator is requested, it creates a copy of the vector and sorts it using std::sort. The iterator accesses that new vector.

PrefixHashRep stores keys in an unordered_map mapping prefixes to ordered sets.

I also added one API change. I added a function MemTableRep::MarkImmutable. This function is called when the rep is added to the immutable list. It doesn't do anything yet, but it seems like that could be useful. In particular, for the vectorrep, it means we could elide the extra copy and just sort in place. The only reason I haven't done that yet is because the use of the ArenaAllocator complicates things (I can elaborate on this if needed).

Test Plan:
make -j32 check
./db_stress --memtablerep=vector
./db_stress --memtablerep=unsorted
./db_stress --memtablerep=prefixhash --prefix_size=10

Reviewers: dhruba, haobo, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12117
2013-08-22 23:10:02 -07:00
Xing Jin af732c7ba8 Add universal compaction to db_stress nightly build
Summary:
Most code change in this diff is code cleanup/rewrite. The logic changes include:

(1) add universal compaction to db_crashtest2.py
(2) randomly set --test_batches_snapshots to be 0 or 1 in db_crashtest2.py. Old codes always use 1.
(3) use different tmp directory as db directory in different runs. I saw some intermittent errors in my local tests. Use of different tmp directory seems to be able to solve the issue.

Test Plan: Have run "make crashtest" for multiple times. Also run "make all check"

Reviewers: emayanke, dhruba, haobo

Reviewed By: emayanke

Differential Revision: https://reviews.facebook.net/D12369
2013-08-20 17:37:49 -07:00
Deon Nicholas b87dcae1a3 Made merge_oprator a shared_ptr; and added TTL unit tests
Test Plan:
- make all check;
- make release;
- make stringappend_test; ./stringappend_test

Reviewers: haobo, emayanke

Reviewed By: haobo

CC: leveldb, kailiu

Differential Revision: https://reviews.facebook.net/D12381
2013-08-20 13:35:28 -07:00
Mayank Agarwal 8a3547d38e API for getting archived log files
Summary: Also expanded class LogFile to have startSequene and FileSize and exposed it publicly

Test Plan: make all check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12087
2013-08-19 13:37:04 -07:00
Deon Nicholas ad48c3c262 Benchmarking for Merge Operator
Summary:
Updated db_bench and utilities/merge_operators.h to allow for dynamic benchmarking
of merge operators in db_bench. Added a new test (--benchmarks=mergerandom), which performs
a bunch of random Merge() operations over random keys. Also added a "--merge_operator=" flag
so that the tester can easily benchmark different merge operators. Currently supports
the PutOperator and UInt64Add operator. Support for stringappend or list append may come later.

Test Plan:
	1. make db_bench
	2. Test the PutOperator (simulating Put) as follows:
./db_bench --benchmarks=fillrandom,readrandom,updaterandom,readrandom,mergerandom,readrandom --merge_operator=put
--threads=2

3. Test the UInt64AddOperator (simulating numeric addition) similarly:
./db_bench --value_size=8 --benchmarks=fillrandom,readrandom,updaterandom,readrandom,mergerandom,readrandom
--merge_operator=uint64add --threads=2

Reviewers: haobo, dhruba, zshao, MarkCallaghan

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11535
2013-08-15 17:13:07 -07:00
Tyler Harter 85d83a150b Update crashtests to match D12267
Summary: I changed the db_stress configs, but forgot to update the scripts using the old configs.

Test Plan: 'make blackbox_crash_test' and 'make whitebox_crash_test' start running normally now (I haven't run them til the end, though).

Reviewers: vamsi

Reviewed By: vamsi

CC: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D12303
2013-08-15 10:14:32 -07:00
Xing Jin 0a5afd1afc Minor fix to current codes
Summary:
Minor fix to current codes, including: coding style, output format,
comments. No major logic change. There are only 2 real changes, please see my inline comments.

Test Plan: make all check

Reviewers: haobo, dhruba, emayanke

Differential Revision: https://reviews.facebook.net/D12297
2013-08-14 23:03:57 -07:00
Tyler Harter 7612d496ff Add prefix scans to db_stress (and bug fix in prefix scan)
Summary: Added support for prefix scans.

Test Plan: ./db_stress --max_key=4096 --ops_per_thread=10000

Reviewers: dhruba, vamsi

Reviewed By: vamsi

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12267
2013-08-14 16:58:36 -07:00
Dhruba Borthakur f3967a5132 Merge remote-tracking branch 'origin' into performance 2013-08-12 09:58:50 -07:00
Haobo Xu 58a0ae06dc [RocksDB] Improve sst_dump to take user key range
Summary: The ability to dump internal keys associated with certain user keys, directly from sst files, is very useful for diagnosis. Will incorporate it directly into ldb later.

Test Plan: run it

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12075
2013-08-08 15:31:12 -07:00
Dhruba Borthakur f5fa26b6a9 Merge branch 'performance' of github.com:facebook/rocksdb into performance
Conflicts:
	db/builder.cc
	db/db_impl.cc
	db/version_set.cc
	include/leveldb/statistics.h
2013-08-07 11:58:06 -07:00
Mayank Agarwal 1d7b4765c3 Expose base db object from ttl wrapper
Summary: rocksdb replicaiton will need this when writing value+TS from master to slave 'as is'

Test Plan: make

Reviewers: dhruba, vamsi, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11919
2013-08-05 18:44:14 -07:00
Dhruba Borthakur 711a30cb30 Merge branch 'master' into performance
Conflicts:
	include/leveldb/options.h
	include/leveldb/statistics.h
	util/options.cc
2013-08-02 10:22:08 -07:00
Mayank Agarwal 59d0b02f8b Expand KeyMayExist to return the proper value if it can be found in memory and also check block_cache
Summary: Removed KeyMayExistImpl because KeyMayExist demanded Get like semantics now. Removed no_io from memtable and imm because we need the proper value now and shouldn't just stop when we see Merge in memtable. Added checks to block_cache. Updated documentation and unit-test

Test Plan: make all check;db_stress for 1 hour

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11853
2013-08-01 09:07:46 -07:00
Mayank Agarwal f3baeecd44 Adding filter_deletes to crash_tests run in jenkins
Summary: filter_deletes options introduced in db_stress makes it drop Deletes on key if KeyMayExist(key) returns false on the key. code change was simple and tested so not wasting reviewer's time.

Test Plan: maek crash_test; python tools/db_crashtest[1|2].py

CC: dhruba, vamsi

Differential Revision: https://reviews.facebook.net/D11769
2013-07-23 13:49:16 -07:00
Mayank Agarwal bf66c10b13 Use KeyMayExist for WriteBatch-Deletes
Summary:
Introduced KeyMayExist checking during writebatch-delete and removed from Outer Delete API because it uses writebatch-delete.
Added code to skip getting Table from disk if not already present in table_cache.
Some renaming of variables.
Introduced KeyMayExistImpl which allows checking since specified sequence number in GetImpl useful to check partially written writebatch.
Changed KeyMayExist to not be pure virtual and provided a default implementation.
Expanded unit-tests in db_test to check appropriately.
Ran db_stress for 1 hour with ./db_stress --max_key=100000 --ops_per_thread=10000000 --delpercent=50 --filter_deletes=1 --statistics=1.

Test Plan: db_stress;make check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb, xjin

Differential Revision: https://reviews.facebook.net/D11745
2013-07-23 13:36:50 -07:00
Dhruba Borthakur 4a745a5666 Merge branch 'master' into performance
Conflicts:
	db/version_set.cc
	include/leveldb/options.h
	util/options.cc
2013-07-17 15:05:57 -07:00
Mayank Agarwal 2a986919d6 Make rocksdb-deletes faster using bloom filter
Summary:
Wrote a new function in db_impl.c-CheckKeyMayExist that calls Get but with a new parameter turned on which makes Get return false only if bloom filters can guarantee that key is not in database. Delete calls this function and if the option- deletes_use_filter is turned on and CheckKeyMayExist returns false, the delete will be dropped saving:
1. Put of delete type
2. Space in the db,and
3. Compaction time

Test Plan:
make all check;
will run db_stress and db_bench and enhance unit-test once the basic design gets approved

Reviewers: dhruba, haobo, vamsi

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11607
2013-07-11 12:11:11 -07:00
Mayank Agarwal 821889e207 Print complete statistics in db_stress
Summary: db_stress should alos print complete statistics like db_bench. Needed this when I wanted to measure number of delete-IOs dropped due to CheckKeyMayExist to be introduced to rocksdb codebase later- to make deltes in rocksdb faster

Test Plan: make db_stress;./db_stress --max_key=100 --ops_per_thread=1000 --statistics=1

Reviewers: sheki, dhruba, vamsi, haobo

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D11655
2013-07-10 18:07:13 -07:00
Dhruba Borthakur 116ec527f2 Renamed 'hybrid_compaction' tp be "Universal Compaction'.
Summary:
All the universal compaction parameters are encapsulated in
a new file universal_compaction.h

Test Plan:
make check
2013-07-03 15:47:53 -07:00
Dhruba Borthakur 47c4191fe8 Reduce write amplification by merging files in L0 back into L0
Summary:
There is a new option called hybrid_mode which, when switched on,
causes HBase style compactions.  Files from L0 are
compacted back into L0. This meat of this compaction algorithm
is in PickCompactionHybrid().

All files reside in L0. That means all files have overlapping
keys. Each file has a time-bound, i.e. each file contains a
range of keys that were inserted around the same time. The
start-seqno and the end-seqno refers to the timeframe when
these keys were inserted.  Files that have contiguous seqno
are compacted together into a larger file. All files are
ordered from most recent to the oldest.

The current compaction algorithm starts to look for
candidate files starting from the most recent file. It continues to
add more files to the same compaction run as long as the
sum of the files chosen till now is smaller than the next
candidate file size. This logic needs to be debated
and validated.

The above logic should reduce write amplification to a
large extent... will publish numbers shortly.

Test Plan: dbstress runs for 6 hours with no data corruption (tested so far).

Differential Revision: https://reviews.facebook.net/D11289
2013-06-30 20:07:04 -07:00
Haobo Xu 0f78fad9f5 [RocksDB] add back --mmap_read options to crashtest
Summary: As title, now that db_stress supports --map_read properly

Test Plan: make crash_test

Reviewers: vamsi, emayanke, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11391
2013-06-19 16:15:59 -07:00
Haobo Xu 96be2c4ee0 [RocksDB] Add mmap_read option for db_stress
Summary: as title, also removed an incorrect assertion

Test Plan: make check; db_stress --mmap_read=1; db_stress --mmap_read=0

Reviewers: dhruba, emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11367
2013-06-19 10:28:32 -07:00
Dhruba Borthakur 836534debd Enhance dbstress to allow specifying compaction trigger for L0.
Summary:
Rocksdb allos specifying the number of files in L0 that triggers
compactions. Expose this api as a command line parameter for
running db_stress.

Test Plan: Run test

Reviewers: sheki, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11343
2013-06-17 14:15:09 -07:00