Commit graph

416 commits

Author SHA1 Message Date
Andrew Kryczka 5d6005c780 Add WriteOptions::protection_bytes_per_key (#10037)
Summary:
Added an option, `WriteOptions::protection_bytes_per_key`, that controls how many bytes per key we use for integrity protection in `WriteBatch`. It takes effect when `WriteBatch::GetProtectionBytesPerKey() == 0`.

Currently the only supported value is eight. Invoking a user API with it set to any other nonzero value will result in `Status::NotSupported` returned to the user.

There is also a bug fix for integrity protection with `inplace_callback`, where we forgot to take into account the possible change in varint length when calculating KV checksum for the final encoded buffer.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10037

Test Plan:
- Manual
  - Set default value of `WriteOptions::protection_bytes_per_key` to eight and ran `make check -j24`
  - Enabled in MyShadow for 1+ week
- Automated
  - Unit tests have a `WriteMode` that enables the integrity protection via `WriteOptions`
  - Crash test - in most cases, use `WriteOptions::protection_bytes_per_key` to enable integrity protection

Reviewed By: cbi42

Differential Revision: D36614569

Pulled By: ajkr

fbshipit-source-id: 8650087ceac9b61b560f1e5fafe5e1baf9c725fb
2022-06-16 23:10:07 -07:00
Yanqin Jin 1777e5f7e9 Snapshots with user-specified timestamps (#9879)
Summary:
In RocksDB, keys are associated with (internal) sequence numbers which denote when the keys are written
to the database. Sequence numbers in different RocksDB instances are unrelated, thus not comparable.

It is nice if we can associate sequence numbers with their corresponding actual timestamps. One thing we can
do is to support user-defined timestamp, which allows the applications to specify the format of custom timestamps
and encode a timestamp with each key. More details can be found at https://github.com/facebook/rocksdb/wiki/User-defined-Timestamp-%28Experimental%29.

This PR provides a different but complementary approach. We can associate rocksdb snapshots (defined in
https://github.com/facebook/rocksdb/blob/7.2.fb/include/rocksdb/snapshot.h#L20) with **user-specified** timestamps.
Since a snapshot is essentially an object representing a sequence number, this PR establishes a bi-directional mapping between sequence numbers and timestamps.

In the past, snapshots are usually taken by readers. The current super-version is grabbed, and a `rocksdb::Snapshot`
object is created with the last published sequence number of the super-version. You can see that the reader actually
has no good idea of what timestamp to assign to this snapshot, because by the time the `GetSnapshot()` is called,
an arbitrarily long period of time may have already elapsed since the last write, which is when the last published
sequence number is written.

This observation motivates the creation of "timestamped" snapshots on the write path. Currently, this functionality is
exposed only to the layer of `TransactionDB`. Application can tell RocksDB to create a snapshot when a transaction
commits, effectively associating the last sequence number with a timestamp. It is also assumed that application will
ensure any two snapshots with timestamps should satisfy the following:
```
snapshot1.seq < snapshot2.seq iff. snapshot1.ts < snapshot2.ts
```

If the application can guarantee that when a reader takes a timestamped snapshot, there is no active writes going on
in the database, then we also allow the user to use a new API `TransactionDB::CreateTimestampedSnapshot()` to create
a snapshot with associated timestamp.

Code example
```cpp
// Create a timestamped snapshot when committing transaction.
txn->SetCommitTimestamp(100);
txn->SetSnapshotOnNextOperation();
txn->Commit();

// A wrapper API for convenience
Status Transaction::CommitAndTryCreateSnapshot(
    std::shared_ptr<TransactionNotifier> notifier,
    TxnTimestamp ts,
    std::shared_ptr<const Snapshot>* ret);

// Create a timestamped snapshot if caller guarantees no concurrent writes
std::pair<Status, std::shared_ptr<const Snapshot>> snapshot = txn_db->CreateTimestampedSnapshot(100);
```

The snapshots created in this way will be managed by RocksDB with ref-counting and potentially shared with
other readers. We provide the following APIs for readers to retrieve a snapshot given a timestamp.
```cpp
// Return the timestamped snapshot correponding to given timestamp. If ts is
// kMaxTxnTimestamp, then we return the latest timestamped snapshot if present.
// Othersise, we return the snapshot whose timestamp is equal to `ts`. If no
// such snapshot exists, then we return null.
std::shared_ptr<const Snapshot> TransactionDB::GetTimestampedSnapshot(TxnTimestamp ts) const;
// Return the latest timestamped snapshot if present.
std::shared_ptr<const Snapshot> TransactionDB::GetLatestTimestampedSnapshot() const;
```

We also provide two additional APIs for stats collection and reporting purposes.

```cpp
Status TransactionDB::GetAllTimestampedSnapshots(
    std::vector<std::shared_ptr<const Snapshot>>& snapshots) const;
// Return timestamped snapshots whose timestamps fall in [ts_lb, ts_ub) and store them in `snapshots`.
Status TransactionDB::GetTimestampedSnapshots(
    TxnTimestamp ts_lb,
    TxnTimestamp ts_ub,
    std::vector<std::shared_ptr<const Snapshot>>& snapshots) const;
```

To prevent the number of timestamped snapshots from growing infinitely, we provide the following API to release
timestamped snapshots whose timestamps are older than or equal to a given threshold.
```cpp
void TransactionDB::ReleaseTimestampedSnapshotsOlderThan(TxnTimestamp ts);
```

Before shutdown, RocksDB will release all timestamped snapshots.

Comparison with user-defined timestamp and how they can be combined:
User-defined timestamp persists every key with a timestamp, while timestamped snapshots maintain a volatile
mapping between snapshots (sequence numbers) and timestamps.
Different internal keys with the same user key but different timestamps will be treated as different by compaction,
thus a newer version will not hide older versions (with smaller timestamps) unless they are eligible for garbage collection.
In contrast, taking a timestamped snapshot at a certain sequence number and timestamp prevents all the keys visible in
this snapshot from been dropped by compaction. Here, visible means (seq < snapshot and most recent).
The timestamped snapshot supports the semantics of reading at an exact point in time.

Timestamped snapshots can also be used with user-defined timestamp.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9879

Test Plan:
```
make check
TEST_TMPDIR=/dev/shm make crash_test_with_txn
```

Reviewed By: siying

Differential Revision: D35783919

Pulled By: riversand963

fbshipit-source-id: 586ad905e169189e19d3bfc0cb0177a7239d1bd4
2022-06-10 16:07:03 -07:00
Yu Zhang a101c9de60 Return "invalid argument" when read timestamp is too old (#10109)
Summary:
With this change, when a given read timestamp is smaller than the column-family's full_history_ts_low, Get(), MultiGet() and iterators APIs will return Status::InValidArgument().
Test plan
```
$COMPILE_WITH_ASAN=1 make -j24 all
$./db_with_timestamp_basic_test --gtest_filter=DBBasicTestWithTimestamp.UpdateFullHistoryTsLow
$ make -j24 check
```

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10109

Reviewed By: riversand963

Differential Revision: D36901126

Pulled By: jowlyzhang

fbshipit-source-id: 255feb1a66195351f06c1d0e42acb1ff74527f86
2022-06-06 14:36:22 -07:00
Yanqin Jin 3e02c6e05a Point-lookup returns timestamps of Delete and SingleDelete (#10056)
Summary:
If caller specifies a non-null `timestamp` argument in `DB::Get()` or a non-null `timestamps` in `DB::MultiGet()`,
RocksDB will return the timestamps of the point tombstones.

Note: DeleteRange is still unsupported.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10056

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D36677956

Pulled By: riversand963

fbshipit-source-id: 2d7af02cc7237b1829cd269086ea895a49d501ae
2022-06-03 20:00:42 -07:00
Jay Zhuang 0adac6f88e Deflake Transaction stress tests (#10063)
Summary:
TSAN test is slower, for `TransactionStressTest` and
`DeadlockStress`, they're reaching the timeout limit of 600 seconds.
Decreasing the transaction test number.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10063

Test Plan: CI

Reviewed By: ajkr

Differential Revision: D36711727

Pulled By: jay-zhuang

fbshipit-source-id: 600f82a6d32108f52fbe5572fcc7497607b7fe98
2022-05-30 12:34:43 -07:00
XieJiSS 8b1df101da fix: build on risc-v (#9215)
Summary:
Patch is modified from ~~https://reviews.llvm.org/file/data/du5ol5zctyqw53ma7dwz/PHID-FILE-knherxziu4tl4erti5ab/file~~

Tested on Arch Linux riscv64gc (qemu)

UPDATE: Seems like the above link is broken, so I tried to search for a link pointing to the original merge request. It turned out to me that the LLVM guys are cherry-picking from `google/benchmark`, and the upstream should be this:

808571a52f/src/cycleclock.h (L190)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9215

Reviewed By: siying, jay-zhuang

Differential Revision: D34170586

Pulled By: riversand963

fbshipit-source-id: 41b16b9f7f3bb0f3e7b26bb078eb575499c0f0f4
2022-05-17 17:33:01 -07:00
mrambacher b11ff347b4 Use STATIC_AVOID_DESTRUCTION for static objects with non-trivial destructors (#9958)
Summary:
Changed the static objects that had non-trivial destructors to use the STATIC_AVOID_DESTRUCTION construct.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9958

Reviewed By: pdillinger

Differential Revision: D36442982

Pulled By: mrambacher

fbshipit-source-id: 029d47b1374d30d198bfede369a4c0ae7a4eb519
2022-05-17 09:39:22 -07:00
sdong 736a7b5433 Remove own ToString() (#9955)
Summary:
ToString() is created as some platform doesn't support std::to_string(). However, we've already used std::to_string() by mistake for 16 months (in db/db_info_dumper.cc). This commit just remove ToString().

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9955

Test Plan: Watch CI tests

Reviewed By: riversand963

Differential Revision: D36176799

fbshipit-source-id: bdb6dcd0e3a3ab96a1ac810f5d0188f684064471
2022-05-06 13:03:58 -07:00
Yanqin Jin 2b5df21e95 Remove ifdef for try_emplace after upgrading to c++17 (#9932)
Summary:
Test plan
make check

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9932

Reviewed By: ajkr

Differential Revision: D36085404

Pulled By: riversand963

fbshipit-source-id: 2ece14ca0e2e4c1288339ff79e7e126b76eaf786
2022-05-02 19:39:24 -07:00
Yanqin Jin 2b5c29f9f3 Enforce the contract of SingleDelete (#9888)
Summary:
Enforce the contract of SingleDelete so that they are not mixed with
Delete for the same key. Otherwise, it will lead to undefined behavior.
See https://github.com/facebook/rocksdb/wiki/Single-Delete#notes.

Also fix unit tests and write-unprepared.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9888

Test Plan: make check

Reviewed By: ajkr

Differential Revision: D35837817

Pulled By: riversand963

fbshipit-source-id: acd06e4dcba8cb18df92b44ed18c57e10e5a7635
2022-04-28 14:48:27 -07:00
Anvesh Komuravelli aafb377bb5 Update protection info on recovered logs data (#9875)
Summary:
Update protection info on recovered logs data

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9875

Test Plan:
- Benchmark setup: `TEST_TMPDIR=/dev/shm/100MB_WAL_DB/ ./db_bench -benchmarks=fillrandom -write_buffer_size=1048576000`
- Benchmark command: `TEST_TMPDIR=/dev/shm/100MB_WAL_DB/ /usr/bin/time ./db_bench -use_existing_db=true -benchmarks=overwrite -write_buffer_size=1048576000 -writes=1 -report_open_timing=true`
- Results before this PR
```
OpenDb:     2350.14 milliseconds
OpenDb:     2296.94 milliseconds
OpenDb:     2184.29 milliseconds
OpenDb:     2167.59 milliseconds
OpenDb:     2231.24 milliseconds
OpenDb:     2109.57 milliseconds
OpenDb:     2197.71 milliseconds
OpenDb:     2120.8 milliseconds
OpenDb:     2148.12 milliseconds
OpenDb:     2207.95 milliseconds
```
- Results after this PR
```
OpenDb:     2424.52 milliseconds
OpenDb:     2359.84 milliseconds
OpenDb:     2317.68 milliseconds
OpenDb:     2339.4 milliseconds
OpenDb:     2325.36 milliseconds
OpenDb:     2321.06 milliseconds
OpenDb:     2353.98 milliseconds
OpenDb:     2344.64 milliseconds
OpenDb:     2384.09 milliseconds
OpenDb:     2428.58 milliseconds
```

Mean regressed 7.2% (2201.4 -> 2359.9)

Reviewed By: ajkr

Differential Revision: D36012787

Pulled By: akomurav

fbshipit-source-id: d2aba09f29c6beb2fd0fe8e1e359be910b4ef02a
2022-04-28 14:42:00 -07:00
Yanqin Jin 94e245a14d Improve stress test for MultiOpsTxnsStressTest (#9829)
Summary:
Adds more coverage to `MultiOpsTxnsStressTest` with a focus on write-prepared transactions.

1. Add a hack to manually evict commit cache entries. We currently cannot assign small values to `wp_commit_cache_bits` because it requires a prepared transaction to commit within a certain range of sequence numbers, otherwise it will throw.
2. Add coverage for commit-time-write-batch. If write policy is write-prepared, we need to set `use_only_the_last_commit_time_batch_for_recovery` to true.
3. After each flush/compaction, verify data consistency. This is possible since data size can be small: default numbers of primary/secondary keys are just 1000.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9829

Test Plan:
```
TEST_TMPDIR=/dev/shm/rocksdb_crashtest_blackbox/ make blackbox_crash_test_with_multiops_wp_txn
```

Reviewed By: pdillinger

Differential Revision: D35806678

Pulled By: riversand963

fbshipit-source-id: d7fde7a29fda0fb481a61f553e0ca0c47da93616
2022-04-27 17:50:54 -07:00
Herman Lee d9d456de49 Fix locktree accesses to PessimisticTransactions (#9898)
Summary:
The current locktree implementation stores the address of the
PessimisticTransactions object as the TXNID. However, when a transaction
is blocked on a lock, it records the list of waitees with conflicting
locks using the rocksdb assigned TransactionID. This is performed by
calling GetID() on PessimisticTransactions objects of the waitees,
and then recorded in the waiter's list.

However, there is no guarantee the objects are valid when recording the
waitee list during the conflict callbacks because the waitee
could have released the lock and freed the PessimisticTransactions
object.

The waitee/txnid values are only valid PessimisticTransaction objects
while the mutex for the root of the locktree is held.

The simplest fix for this problem is to use the address of the
PessimisticTransaction as the TransactionID so that it is consistent
with its usage in the locktree. The TXNID is only converted back to a
PessimisticTransaction for the report_wait callbacks. Since
these callbacks are now all made within the critical section where the
lock_request queue mutx is held, these conversions will be safe.
Otherwise, only the uint64_t TXNID of the waitee is registerd
with the waiter transaction. The PessimisitcTransaction object of the
waitee is never referenced.

The main downside of this approach is the TransactionID will not change
if the PessimisticTransaction object is reused for new transactions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9898

Test Plan:
Add a new test case and run unit tests.
Also verified with MyRocks workloads using range locks that the
crash no longer happens.

Reviewed By: riversand963

Differential Revision: D35950376

Pulled By: hermanlee

fbshipit-source-id: 8c9cae272e23e487fc139b6a8ed5b8f8f24b1570
2022-04-27 09:12:52 -07:00
Yanqin Jin d13825e586 Add rollback_deletion_type_callback to TxnDBOptions (#9873)
Summary:
This PR does not affect write-committed.

Add a member, `rollback_deletion_type_callback` to TransactionDBOptions
so that a write-prepared transaction, when rolling back, can call this
callback to decide if a `Delete` or `SingleDelete` should be used to
cancel a prior `Put` written to the database during prepare phase.

The purpose of this PR is to prevent mixing `Delete` and `SingleDelete`
for the same key, causing undefined behaviors. Without this PR, the
following can happen:

```
// The application always issues SingleDelete when deleting keys.

txn1->Put('a');
txn1->Prepare(); // writes to memtable and potentially gets flushed/compacted to Lmax
txn1->Rollback();  // inserts DELETE('a')

txn2->Put('a');
txn2->Commit();  // writes to memtable and potentially gets flushed/compacted
```

In the database, we may have
```
L0:   [PUT('a', s=100)]
L1:   [DELETE('a', s=90)]
Lmax: [PUT('a', s=0)]
```

If a compaction compacts L0 and L1, then we have
```
L1:    [PUT('a', s=100)]
Lmax:  [PUT('a', s=0)]
```

If a future transaction issues a SingleDelete, we have
```
L0:    [SD('a', s=110)]
L1:    [PUT('a', s=100)]
Lmax:  [PUT('a', s=0)]
```

Then, a compaction including L0, L1 and Lmax leads to
```
Lmax:  [PUT('a', s=0)]
```

which is incorrect.

Similar bugs reported and addressed in
https://github.com/cockroachdb/pebble/issues/1255. Based on our team's
current priority, we have decided to take this approach for now. We may
come back and revisit in the future.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9873

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D35762170

Pulled By: riversand963

fbshipit-source-id: b28d56eefc786b53c9844b9ef4a7807acdd82c8d
2022-04-20 18:57:32 -07:00
Peter Dillinger efd035164b Meta-internal folly integration with F14FastMap (#9546)
Summary:
Especially after updating to C++17, I don't see a compelling case for
*requiring* any folly components in RocksDB. I was able to purge the existing
hard dependencies, and it can be quite difficult to strip out non-trivial components
from folly for use in RocksDB. (The prospect of doing that on F14 has changed
my mind on the best approach here.)

But this change creates an optional integration where we can plug in
components from folly at compile time, starting here with F14FastMap to replace
std::unordered_map when possible (probably no public APIs for example). I have
replaced the biggest CPU users of std::unordered_map with compile-time
pluggable UnorderedMap which will use F14FastMap when USE_FOLLY is set.
USE_FOLLY is always set in the Meta-internal buck build, and a simulation of
that is in the Makefile for public CI testing. A full folly build is not needed, but
checking out the full folly repo is much simpler for getting the dependency,
and anything else we might want to optionally integrate in the future.

Some picky details:
* I don't think the distributed mutex stuff is actually used, so it was easy to remove.
* I implemented an alternative to `folly::constexpr_log2` (which is much easier
in C++17 than C++11) so that I could pull out the hard dependencies on
`ConstexprMath.h`
* I had to add noexcept move constructors/operators to some types to make
F14's complainUnlessNothrowMoveAndDestroy check happy, and I added a
macro to make that easier in some common cases.
* Updated Meta-internal buck build to use folly F14Map (always)

No updates to HISTORY.md nor INSTALL.md as this is not (yet?) considered a
production integration for open source users.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9546

Test Plan:
CircleCI tests updated so that a couple of them use folly.

Most internal unit & stress/crash tests updated to use Meta-internal latest folly.
(Note: they should probably use buck but they currently use Makefile.)

Example performance improvement: when filter partitions are pinned in cache,
they are tracked by PartitionedFilterBlockReader::filter_map_ and we can build
a test that exercises that heavily. Build DB with

```
TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom -num=10000000 -disable_wal=1 -write_buffer_size=30000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -partition_index_and_filters
```

and test with (simultaneous runs with & without folly, ~20 times each to see
convergence)

```
TEST_TMPDIR=/dev/shm/rocksdb ./db_bench_folly -readonly -use_existing_db -benchmarks=readrandom -num=10000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -partition_index_and_filters -duration=40 -pin_l0_filter_and_index_blocks_in_cache
```

Average ops/s no folly: 26229.2
Average ops/s with folly: 26853.3 (+2.4%)

Reviewed By: ajkr

Differential Revision: D34181736

Pulled By: pdillinger

fbshipit-source-id: ffa6ad5104c2880321d8a1aa7187e00ab0d02e94
2022-04-13 07:34:01 -07:00
Yanqin Jin 1a1c5bda23 Disallow commit-time-batch for write-prepared/write-unprepared txn conditionally (#9794)
Summary:
For write-prepared/write-unprepared transactions,
GetCommitTimeWriteBatch() can be used only if the transaction is started
with `TransactionOptions::use_only_the_last_commit_time_batch_for_recovery` set
to true. Otherwise, it is possible that multiple uncommitted versions of the
same key exist in the database. During bottommost compaction, RocksDB may
set the sequence numbers of both to zero once they become committed, causing
output SST file to have two identical internal keys.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9794

Test Plan:
make check
pay special attention to the following
```
transaction_test --gtest_filter=MySQLStyleTransactionTest/MySQLStyleTransactionTest.TransactionStressTest/*
```

Reviewed By: lth

Differential Revision: D35327214

Pulled By: riversand963

fbshipit-source-id: 3bae00a28359c10e96e4c6f676d20de5610d8a0f
2022-04-05 11:10:20 -07:00
Yanqin Jin 565fcead22 Fix clang-analyze by adding assertion (#9682)
Summary:
Clang-analyze complains about potential nullptr dereference.
Fix by adding an assertion to make clang happy.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9682

Test Plan: USE_CLANG=1 make -j20 analyze_incremental

Reviewed By: ltamasi

Differential Revision: D34755210

Pulled By: riversand963

fbshipit-source-id: 948e1899846ee1aa05a1b500a11ff43b0b412e0a
2022-03-09 10:13:02 -08:00
Yanqin Jin 3b6dc049f7 Support user-defined timestamps in write-committed txns (#9629)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9629

Pessimistic transactions use pessimistic concurrency control, i.e. locking. Keys are
locked upon first operation that writes the key or has the intention of writing. For example,
`PessimisticTransaction::Put()`, `PessimisticTransaction::Delete()`,
`PessimisticTransaction::SingleDelete()` will write to or delete a key, while
`PessimisticTransaction::GetForUpdate()` is used by application to indicate
to RocksDB that the transaction has the intention of performing write operation later
in the same transaction.
Pessimistic transactions support two-phase commit (2PC). A transaction can be
`Prepared()`'ed and then `Commit()`. The prepare phase is similar to a promise: once
`Prepare()` succeeds, the transaction has acquired the necessary resources to commit.
The resources include locks, persistence of WAL, etc.
Write-committed transaction is the default pessimistic transaction implementation. In
RocksDB write-committed transaction, `Prepare()` will write data to the WAL as a prepare
section. `Commit()` will write a commit marker to the WAL and then write data to the
memtables. While writing to the memtables, different keys in the transaction's write batch
will be assigned different sequence numbers in ascending order.
Until commit/rollback, the transaction holds locks on the keys so that no other transaction
can write to the same keys. Furthermore, the keys' sequence numbers represent the order
in which they are committed and should be made visible. This is convenient for us to
implement support for user-defined timestamps.
Since column families with and without timestamps can co-exist in the same database,
a transaction may or may not involve timestamps. Based on this observation, we add two
optional members to each `PessimisticTransaction`, `read_timestamp_` and
`commit_timestamp_`. If no key in the transaction's write batch has timestamp, then
setting these two variables do not have any effect. For the rest of this commit, we discuss
only the cases when these two variables are meaningful.

read_timestamp_ is used mainly for validation, and should be set before first call to
`GetForUpdate()`. Otherwise, the latter will return non-ok status. `GetForUpdate()` calls
`TryLock()` that can verify if another transaction has written the same key since
`read_timestamp_` till this call to `GetForUpdate()`. If another transaction has indeed
written the same key, then validation fails, and RocksDB allows this transaction to
refine `read_timestamp_` by increasing it. Note that a transaction can still use `Get()`
with a different timestamp to read, but the result of the read should not be used to
determine data that will be written later.

commit_timestamp_ must be set after finishing writing and before transaction commit.
This applies to both 2PC and non-2PC cases. In the case of 2PC, it's usually set after
prepare phase succeeds.

We currently require that the commit timestamp be chosen after all keys are locked. This
means we disallow the `TransactionDB`-level APIs if user-defined timestamp is used
by the transaction. Specifically, calling `PessimisticTransactionDB::Put()`,
`PessimisticTransactionDB::Delete()`, `PessimisticTransactionDB::SingleDelete()`,
etc. will return non-ok status because they specify timestamps before locking the keys.
Users are also prompted to use the `Transaction` APIs when they receive the non-ok status.

Reviewed By: ltamasi

Differential Revision: D31822445

fbshipit-source-id: b82abf8e230216dc89cc519564a588224a88fd43
2022-03-08 16:20:59 -08:00
Yanqin Jin 6f12599863 Support WBWI for keys having timestamps (#9603)
Summary:
This PR supports inserting keys to a `WriteBatchWithIndex` for column families that enable user-defined timestamps
and reading the keys back. **The index does not have timestamps.**

Writing a key to WBWI is unchanged, because the underlying WriteBatch already supports it.
When reading the keys back, we need to make sure to distinguish between keys with and without timestamps before
comparison.

When user calls `GetFromBatchAndDB()`, no timestamp is needed to query the batch, but a timestamp has to be
provided to query the db. The assumption is that data in the batch must be newer than data from the db.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9603

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D34354849

Pulled By: riversand963

fbshipit-source-id: d25d1f84e2240ce543e521fa30595082fb8db9a0
2022-02-22 14:23:01 -08:00
Yanqin Jin 1cda273dc3 Fix a silent data loss for write-committed txn (#9571)
Summary:
The following sequence of events can cause silent data loss for write-committed
transactions.
```
Time    thread 1                                       bg flush
 |   db->Put("a")
 |   txn = NewTxn()
 |   txn->Put("b", "v")
 |   txn->Prepare()       // writes only to 5.log
 |   db->SwitchMemtable() // memtable 1 has "a"
 |                        // close 5.log,
 |                        // creates 8.log
 |   trigger flush
 |                                                  pick memtable 1
 |                                                  unlock db mutex
 |                                                  write new sst
 |   txn->ctwb->Put("gtid", "1") // writes 8.log
 |   txn->Commit() // writes to 8.log
 |                 // writes to memtable 2
 |                                               compute min_log_number_to_keep_2pc, this
 |                                               will be 8 (incorrect).
 |
 |                                             Purge obsolete wals, including 5.log
 |
 V
```

At this point, writes of txn exists only in memtable. Close db without flush because db thinks the data in
memtable are backed by log. Then reopen, the writes are lost except key-value pair {"gtid"->"1"},
only the commit marker of txn is in 8.log

The reason lies in `PrecomputeMinLogNumberToKeep2PC()` which calls `FindMinPrepLogReferencedByMemTable()`.
In the above example, when bg flush thread tries to find obsolete wals, it uses the information
computed by `PrecomputeMinLogNumberToKeep2PC()`. The return value of `PrecomputeMinLogNumberToKeep2PC()`
depends on three components
- `PrecomputeMinLogNumberToKeepNon2PC()`. This represents the WAL that has unflushed data. As the name of this method suggests, it does not account for 2PC. Although the keys reside in the prepare section of a previous WAL, the column family references the current WAL when they are actually inserted into the memtable during txn commit.
- `prep_tracker->FindMinLogContainingOutstandingPrep()`. This represents the WAL with a prepare section but the txn hasn't committed.
- `FindMinPrepLogReferencedByMemTable()`. This represents the WAL on which some memtables (mutable and immutable) depend for their unflushed data.

The bug lies in `FindMinPrepLogReferencedByMemTable()`. Originally, this function skips checking the column families
that are being flushed, but the unit test added in this PR shows that they should not be. In this unit test, there is
only the default column family, and one of its memtables has unflushed data backed by a prepare section in 5.log.
We should return this information via `FindMinPrepLogReferencedByMemTable()`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9571

Test Plan:
```
./transaction_test --gtest_filter=*/TransactionTest.SwitchMemtableDuringPrepareAndCommit_WC/*
make check
```

Reviewed By: siying

Differential Revision: D34235236

Pulled By: riversand963

fbshipit-source-id: 120eb21a666728a38dda77b96276c6af72b008b1
2022-02-16 23:08:58 -08:00
Yanqin Jin 241b5aa15a Timestamp-based validation for pessimistic txn (#9562)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9562

With per-transaction `read_timestamp_`, it is possible to perform transaction validation after
locking a key in addition to sequence-based validation. Specifically, if a transaction has a
read_timestamp, then we perform timestamp-based validation as well after the key is locked
via `GetForUpdate()`. This is to make sure that no other transaction has modified the key and
committed successfully since the read timestamp (but before the locking operation) which
 represents a consistent view of the database.

Reviewed By: ltamasi

Differential Revision: D31822034

fbshipit-source-id: c6f1828b7fc23e4f85e2d1ed73ff51464a058d91
2022-02-14 17:32:47 -08:00
Yanqin Jin d6e1e6f37a Add commit_timestamp and read_timestamp to Pessimistic transaction (#9537)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9537

Add `Transaction::SetReadTimestampForValidation()` and
`Transaction::SetCommitTimestamp()` APIs with default implementation
returning `Status::NotSupported()`. Currently, calling these two APIs do not
have any effect.

Also add checks to `PessimisticTransactionDB`
to enforce that column families in the same db either
- disable user-defined timestamp
- enable 64-bit timestamp

Just to clarify, a `PessimisticTransactionDB` can have some column families without
timestamps as well as column families that enable timestamp.

Each `PessimisticTransaction` can have two optional timestamps, `read_timestamp_`
used for additional validation and `commit_timestamp_` which denotes when the transaction commits.
For now, we are going to support `WriteCommittedTxn` (in a series of subsequent PRs)

Once set, we do not allow decreasing `read_timestamp_`. The `commit_timestamp_` must be
 greater than `read_timestamp_` for each transaction and must be set before commit, unless
the transaction does not involve any column family that enables user-defined timestamp.

TransactionDB builds on top of RocksDB core `DB` layer. Though `DB` layer assumes
that user-defined timestamps are byte arrays, `TransactionDB` uses uint64_t to store
timestamps. When they are passed down, they are still interpreted as
byte-arrays by `DB`.

Reviewed By: ltamasi

Differential Revision: D31567959

fbshipit-source-id: b0b6b69acab5d8e340cf174f33e8b09f1c3d3502
2022-02-11 20:19:15 -08:00
Yanqin Jin 3122cb4358 Revise APIs related to user-defined timestamp (#8946)
Summary:
ajkr reminded me that we have a rule of not including per-kv related data in `WriteOptions`.
Namely, `WriteOptions` should not include information about "what-to-write", but should just
include information about "how-to-write".

According to this rule, `WriteOptions::timestamp` (experimental) is clearly a violation. Therefore,
this PR removes `WriteOptions::timestamp` for compliance.
After the removal, we need to pass timestamp info via another set of APIs. This PR proposes a set
of overloaded functions `Put(write_opts, key, value, ts)`, `Delete(write_opts, key, ts)`, and
`SingleDelete(write_opts, key, ts)`. Planned to add `Write(write_opts, batch, ts)`, but its complexity
made me reconsider doing it in another PR (maybe).

For better checking and returning error early, we also add a new set of APIs to `WriteBatch` that take
extra `timestamp` information when writing to `WriteBatch`es.
These set of APIs in `WriteBatchWithIndex` are currently not supported, and are on our TODO list.

Removed `WriteBatch::AssignTimestamps()` and renamed `WriteBatch::AssignTimestamp()` to
`WriteBatch::UpdateTimestamps()` since this method require that all keys have space for timestamps
allocated already and multiple timestamps can be updated.

The constructor of `WriteBatch` now takes a fourth argument `default_cf_ts_sz` which is the timestamp
size of the default column family. This will be used to allocate space when calling APIs that do not
specify a column family handle.

Also, updated `DB::Get()`, `DB::MultiGet()`, `DB::NewIterator()`, `DB::NewIterators()` methods, replacing
some assertions about timestamp to returning Status code.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8946

Test Plan:
make check
./db_bench -benchmarks=fillseq,fillrandom,readrandom,readseq,deleterandom -user_timestamp_size=8
./db_stress --user_timestamp_size=8 -nooverwritepercent=0 -test_secondary=0 -secondary_catch_up_one_in=0 -continuous_verification_interval=0

Make sure there is no perf regression by running the following
```
./db_bench_opt -db=/dev/shm/rocksdb -use_existing_db=0 -level0_stop_writes_trigger=256 -level0_slowdown_writes_trigger=256 -level0_file_num_compaction_trigger=256 -disable_wal=1 -duration=10 -benchmarks=fillrandom
```

Before this PR
```
DB path: [/dev/shm/rocksdb]
fillrandom   :       1.831 micros/op 546235 ops/sec;   60.4 MB/s
```
After this PR
```
DB path: [/dev/shm/rocksdb]
fillrandom   :       1.820 micros/op 549404 ops/sec;   60.8 MB/s
```

Reviewed By: ltamasi

Differential Revision: D33721359

Pulled By: riversand963

fbshipit-source-id: c131561534272c120ffb80711d42748d21badf09
2022-02-01 22:19:01 -08:00
Sergei Petrunia c9042db619 Range Locking: add support for escalation barriers (#9290)
Summary:
Range Locking supports Lock Escalation. Lock Escalation is invoked when
lock memory is nearly exhausted and it reduced the amount of memory used
by joining adjacent locks.

Bridging the gap between certain locks has adverse effects. For example,
in MyRocks it is not a good idea to bridge the gap between locks in
different indexes, as that get the lock to cover large portions of
indexes, or even entire indexes.

Resolve this by introducing Escalation Barrier. The escalation process
will call the user-provided barrier callback function:
   bool(const Endpoint& a, const Endpoint& b)

If the function returns true, there's a barrier between a and b and Lock
Escalation will not try to bridge the gap between a and b.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9290

Reviewed By: akankshamahajan15

Differential Revision: D33486753

Pulled By: riversand963

fbshipit-source-id: f97910b67aba0579ea1d35f523ca6863d3dd018e
2022-01-14 12:46:09 -08:00
Yanqin Jin 0376869f05 Remove using namespace (#9369)
Summary:
As title.
This is part of an fb-internal task.
First, remove all `using namespace` statements if applicable.
Next, utilize multiple build platforms and see if anything is broken.
Should anything become broken, fix the compilation errors with as little extra change as possible.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9369

Test Plan:
internal build and make check
make clean && make static_lib && cd examples && make all

Reviewed By: pdillinger

Differential Revision: D33517260

Pulled By: riversand963

fbshipit-source-id: 3fc4ce6402a073421dfd9a9b2d1c79441dca7a40
2022-01-12 09:31:12 -08:00
Sergei Petrunia 1b076e82db Expose locktree's wait count in RangeLockManagerHandle::Counters (#9289)
Summary:
locktree is a module providing Range Locking. It has a counter for
the number of times a lock acquisition request was blocked by an
existing conflicting lock and had to wait for it to be released.

Expose this counter in RangeLockManagerHandle::Counters::lock_wait_count.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9289

Reviewed By: jay-zhuang

Differential Revision: D33079182

Pulled By: riversand963

fbshipit-source-id: 25b1a362d9da247536ab5007bd15900b319f139e
2021-12-22 21:14:48 -08:00
Hui Xiao cd85439632 Make TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAcces less flaky (#9281)
Summary:
Context:
[Rapid thread creation and deletion](https://github.com/facebook/rocksdb/blob/6.27.fb/utilities/transactions/write_prepared_transaction_test.cc#L439-L444) in  `SnapshotConcurrentAccessTest.SnapshotConcurrentAcces` inside a [potentially big loop](https://github.com/facebook/rocksdb/blob/6.27.fb/utilities/transactions/write_prepared_transaction_test.cc#L1238-L1248) can lead to heavy-loading the system with many threads due to delay in actually cleaning up thread's resource in the kernel sometime. We ran into some [flaky failure](https://app.circleci.com/pipelines/github/facebook/rocksdb/10383/workflows/136f1005-80a9-4515-aee9-fe36ac6462a1/jobs/253289) in CI and reproduced it by below:

- Command
```
Added `ROCKSDB_NAMESPACE::port::InstallStackTraceHandler();` like https://github.com/facebook/rocksdb/pull/9276
DEBUG_LEVEL=2 make -j56 write_prepared_transaction_test
GTEST_CATCH_EXCEPTIONS=0 ~/gtest-parallel/gtest-parallel -r 200 -w 200 ./write_prepared_transaction_test --gtest_filter=TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
```
- Stack, where `write_prepared_transaction_test.cc:442` in `https://github.com/facebook/rocksdb/issues/9` points to thread creation
```
[ RUN      ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
....terminate called after throwing an instance of 'std::system_error'
  what():  Resource temporarily unavailable
Received signal 6 (Aborted)
#0   /lib/x86_64-linux-gnu/libc.so.6(gsignal+0x38) [0x7fc114f39438]
...
https://github.com/facebook/rocksdb/issues/7   /usr/lib/x86_64-linux-gnu/libstdc++.so.6(+0xb8e73) [0x7fc1158a5e73] ??	??:0
https://github.com/facebook/rocksdb/issues/8   ./write_prepared_transaction_test() [0x4ca86c] std:🧵:thread<rocksdb::WritePreparedTransactionTestBase::SnapshotConcurrentAccessTestInternal(rocksdb::WritePreparedTxnDB*, std::vector<unsigned long, std::allocator<unsigned long> > const&, std::vector<unsigned long, std::allocator<unsigned long> 	 const&, rocksdb::WritePreparedTxnDB::CommitEntry&, unsigned long&, unsigned long, unsigned long, unsigned long, unsigned long)::{lambda()https://github.com/facebook/rocksdb/issues/1}>(rocksdb::WritePreparedTransactionTestBase::SnapshotConcurrentAccessTestInternal(rocksdb::WritePreparedTxnDB*, s	d::vector<unsigned long, std::allocator<unsigned long> > const&, std::vector<unsigned long, std::allocator<unsigned long> > const&, rocksdb::WritePreparedTxnDB::CommitEntry&, unsigned long&, unsigned long, unsigned long, unsigned long, unsigned long)::{l	mbda()https://github.com/facebook/rocksdb/issues/1}&&)	/usr/include/c++/5/thread:137 (discriminator 4)
https://github.com/facebook/rocksdb/issues/9   ./write_prepared_transaction_test() [0x4bb80c] rocksdb::WritePreparedTransactionTestBase::SnapshotConcurrentAccessTestInternal(rocksdb::WritePreparedTxnDB*, std::vector<unsigned long, std::allocator<unsigned long> > const&, std::vector<unsigned long, std::allocator<unsigned long> > const&, rocksdb::W	itePreparedTxnDB::CommitEntry&, unsigned long&, unsigned long, unsigned long, unsigned long, unsigned long)	/home/circleci/project/utilities/transactions/write_prepared_transaction_test.cc:442
https://github.com/facebook/rocksdb/issues/10  ./write_prepared_transaction_test() [0x4407b6] rocksdb::SnapshotConcurrentAccessTest_SnapshotConcurrentAccess_Test::TestBody()	/home/circleci/project/utilities/transactions/write_prepared_transaction_test.cc:1244
...
[109/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1 returned/aborted with exit code -6 (34462 ms)
```

- Move thread 2's work into current thread to avoid half of the thread creation cuz there is no difference in doing so. We expect this can make the thread-creation error less often, even though we can't gurantee it from happening again. Considering this is a trivial change with positive impact, it's still worth landing and monitor if it's enough to solve the problem in reality.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9281

Test Plan:
Before the change, repeating the test 200 times with 200 workers failed
`~/gtest-parallel/gtest-parallel -r 200 -w 200 ./write_prepared_transaction_test --gtest_filter=TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1`

```
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from TwoWriteQueues/SnapshotConcurrentAccessTest
[ RUN      ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
..unknown file: Failure
C++ exception with description "Resource temporarily unavailable" thrown in the test body.
[  FAILED  ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1, where GetParam() = (false, true, 1, 0, 1, 20) (11882 ms)
[----------] 1 test from TwoWriteQueues/SnapshotConcurrentAccessTest (11882 ms total)

[----------] Global test environment tear-down
[==========] 1 test from 1 test case ran. (11882 ms total)
[  PASSED  ] 0 tests.
[  FAILED  ] 1 test, listed below:
[  FAILED  ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1, where GetParam() = (false, true, 1, 0, 1, 20)
```

After the change: repeating the test 200 times with 200 workers didn't fail, even with repeating the "repeating" for 10 times like below
`for i in {1..10}; do ~/gtest-parallel/gtest-parallel -r 200 -w 200 ./write_prepared_transaction_test --gtest_filter=TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1; done`

```
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
```

It does failed when repeating the test 400 times with 400 workers
`~/project$ ~/gtest-parallel/gtest-parallel -r 400 -w 400 ./write_prepared_transaction_test --gtest_filter=TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1`

```
[1/400] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1 (2928 ms)
Note: Google Test filter = TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from TwoWriteQueues/SnapshotConcurrentAccessTest
[ RUN      ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
unknown file: Failure
C++ exception with description "std::bad_alloc" thrown in the test body.
[  FAILED  ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1, where GetParam() = (false, true, 1, 0, 1, 20) (2597 ms)
[----------] 1 test from TwoWriteQueues/SnapshotConcurrentAccessTest (2597 ms total)
```

Reviewed By: ajkr

Differential Revision: D33026776

Pulled By: hx235

fbshipit-source-id: 509f57126392821e835e48396e5bf224f4f5dcac
2021-12-10 12:52:33 -08:00
Yanqin Jin bd513fd075 Add commit marker with timestamp (#9266)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9266

This diff adds a new tag `CommitWithTimestamp`. Currently, there is no API to trigger writing
this tag to WAL, thus it is unavailable to users.
This is an ongoing effort to add user-defined timestamp support to write-committed transactions.
This diff also indicates all column families that may potentially participate in the same
transaction must either disable timestamp or have the same timestamp format, since
`CommitWithTimestamp` tag is followed by a single byte-array denoting the commit
timestamp of the transaction. We will enforce this checking in a future diff. We keep this
diff small.

Reviewed By: ltamasi

Differential Revision: D31721350

fbshipit-source-id: e1450811443647feb6ca01adec4c8aaae270ffc6
2021-12-10 11:05:35 -08:00
Peter Dillinger aec95b8c09 Debug "Resource temporarily unavailable" exception in CircleCI (#9276)
Summary:
This changes write_prepared_transaction_test under CircleCI to
print a stack trace on unhandled exception, so that we can debug rare
exceptions seen in CircleCI:

    [ RUN      ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/24
    .......unknown file: Failure
    C++ exception with description "Resource temporarily unavailable" thrown in the test body.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9276

Test Plan:
manual run test with seeded 'throw', with and without
CIRCLECI=true environment variable

Reviewed By: ajkr, hx235

Differential Revision: D32996993

Pulled By: pdillinger

fbshipit-source-id: e790408ce204b676d3d84a290e41be511b203bfa
2021-12-09 12:58:46 -08:00
lgqss 77c7085594 MemTableList::TrimHistory now use allocated bytes (#9020)
Summary:
Fix a bug when both max_write_buffer_size_to_maintain and max_write_buffer_number_to_maintain are 0.
The bug was introduced in 6.5.0 and  https://github.com/facebook/rocksdb/issues/5022.
Fix https://github.com/facebook/rocksdb/issues/8371

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9020

Reviewed By: pdillinger

Differential Revision: D32767084

Pulled By: ajkr

fbshipit-source-id: c401ee6e2557230e892d0fe8abb4966cbd18e85f
2021-12-02 11:45:39 -08:00
Yanqin Jin 2035798834 Update TransactionUtil::CheckKeyForConflict to also use timestamps (#9162)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9162

Existing TransactionUtil::CheckKeyForConflict() performs only seq-based
conflict checking. If user-defined timestamp is enabled, it should perform
conflict checking based on timestamps too.

Update TransactionUtil::CheckKey-related methods to verify the timestamp of the
latest version of a key is smaller than the read timestamp. Note that
CheckKeysForConflict() is not updated since it's used only by optimistic
transaction, and we do not plan to update it in this upcoming batch of diffs.

Existing GetLatestSequenceForKey() returns the sequence of the latest
version of a specific user key. Since we support user-defined timestamp, we
need to update this method to also return the timestamp (if enabled) of the
latest version of the key. This will be needed for snapshot validation.

Reviewed By: ltamasi

Differential Revision: D31567960

fbshipit-source-id: 2e4a14aed267435a9aa91bc632d2411c01946d44
2021-11-15 12:52:18 -08:00
jsteemann a7478070f3 Fix small issues (#5896)
Summary:
The individual commits in this PR should be self-explanatory.
All small and _very_ low-priority changes.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/5896

Reviewed By: riversand963

Differential Revision: D18065108

Pulled By: mrambacher

fbshipit-source-id: 236b1a1d9d21f982cc08aa67027108dde5eaf280
2021-11-08 12:32:38 -08:00
Yanqin Jin 5237b39d2e Fix assertion error during compaction with write-prepared txn enabled (#9105)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9105

The user contract of SingleDelete is that: a SingleDelete can only be issued to
a key that exists and has NOT been updated. For example, application can insert
one key `key`, and uses a SingleDelete to delete it in the future. The `key`
cannot be updated or removed using Delete.
In reality, especially when write-prepared transaction is being used, things
can get tricky. For example, a prepared transaction already writes `key` to the
memtable after a successful Prepare(). Afterwards, should the transaction
rollback, it will insert a Delete into the memtable to cancel out the prior
Put. Consider the following sequence of operations.

```
// operation sequence 1
Begin txn
Put(key)
Prepare()
Flush()

Rollback txn
Flush()
```

There will be two SSTs resulting from above. One of the contains a PUT, while
the second one contains a Delete. It is also known that releasing a snapshot
can lead to an L0 containing only a SD for a particular key. Consider the
following operations following the above block.

```
// operation sequence 2
db->Put(key)
db->SingleDelete(key)
Flush()
```

The operation sequence 2 can result in an L0 with only the SD.

Should there be a snapshot for conflict checking created before operation
sequence 1, then an attempt to compact the db may hit the assertion failure
below, because ikey_.type is Delete (from a rollback).

```
else if (clear_and_output_next_key_) {
  assert(ikey_.type == kTypeValue || ikey_.type == kTypeBlobIndex);
}
```

To fix the assertion failure, we can skip the SingleDelete if we detect an
earlier Delete in the same snapshot interval.

Reviewed By: ltamasi

Differential Revision: D32056848

fbshipit-source-id: 23620a91e28562d91c45cf7e95f414b54b729748
2021-11-05 15:29:18 -07:00
Yanqin Jin 9b53f14a35 Fixed a bug in CompactionIterator when write-preared transaction is used (#9060)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9060

RocksDB bottommost level compaction may zero out an internal key's sequence if
the key's sequence is in the earliest_snapshot.
In write-prepared transaction, checking the visibility of a certain sequence in
a specific released snapshot may return a "snapshot released" result.
Therefore, it is possible, after a certain sequence of events, a PUT has its
sequence zeroed out, but a subsequent SingleDelete of the same key will still
be output with its original sequence. This violates the ascending order of
keys and leads to incorrect result.

The solution is to use an extra variable `last_key_seq_zeroed_` to track the
information about visibility in earliest snapshot. With this variable, we can
know for sure that a SingleDelete is in the earliest snapshot even if the said
snapshot is released during compaction before processing the SD.

Reviewed By: ltamasi

Differential Revision: D31813016

fbshipit-source-id: d8cff59d6f34e0bdf282614034aaea99be9174e1
2021-11-03 15:55:00 -07:00
Yanqin Jin fdf2a0d7eb Fix a compaction bug for write-prepared txn (#9061)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9061

In write-prepared txn, checking a sequence's visibility in a released (old)
snapshot may return "Snapshot released". Suppose we have two snapshots:

```
earliest_snap < earliest_write_conflict_snap
```

If we release `earliest_write_conflict_snap` but keep `earliest_snap` during
bottommost level compaction, then it is possible that certain sequence of
events can lead to a PUT being seq-zeroed followed by a SingleDelete of the
same key. This violates the ascending order of keys, and will cause data
inconsistency.

Reviewed By: ltamasi

Differential Revision: D31813017

fbshipit-source-id: dc68ba2541d1228489b93cf3edda5f37ed06f285
2021-10-29 15:23:17 -07:00
Jonathan Albrecht e970248602 Add support for building on s390x platform (#8962)
Summary:
This PR adds support for building on s390x including updating travis CI. It uses the previous work in https://github.com/facebook/rocksdb/pull/6168 and adds some more changes to get all current tests (make check and jni tests) to pass. The tests were run with snappy, lz4, bzip2 and zstd all compiled in.

There are a few pieces still needed to get the travis build working that I don't think I can do. adamretter is this something you could help with?

1. A prebuilt https://rocksdb-deps.s3-us-west-2.amazonaws.com/cmake/cmake-3.14.5-Linux-s390x.deb package
2. A https://hub.docker.com/r/evolvedbinary/rocksjava s390x image

Not sure if there is more required for travis. Happy to help in any way I can.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8962

Reviewed By: mrambacher

Differential Revision: D31802198

Pulled By: pdillinger

fbshipit-source-id: 683511466fa6b505f85ba5a9964a268c6151f0c2
2021-10-22 10:13:15 -07:00
Yanqin Jin e1139167ae Inline an empty destructor (#9004)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9004

Inline an empty destructor

Reviewed By: ltamasi

Differential Revision: D31525561

fbshipit-source-id: 3b9e37f06b0c70529a5d2d660de21ea335c73611
2021-10-11 18:14:10 -07:00
Yanqin Jin 1a79839c59 Some code cleanup (#9003)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9003

cleanup some code before real work.

Reviewed By: ltamasi

Differential Revision: D31525563

fbshipit-source-id: 44558b3594f2200adc7d8621b08b06c77e358a27
2021-10-11 18:14:10 -07:00
mrambacher 13ae16c315 Cleanup includes in dbformat.h (#8930)
Summary:
This header file was including everything and the kitchen sink when it did not need to.  This resulted in many places including this header when they needed other pieces instead.

Cleaned up this header to only include what was needed and fixed up the remaining code to include what was now missing.

Hopefully, this sort of code hygiene cleanup will speed up the builds...

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8930

Reviewed By: pdillinger

Differential Revision: D31142788

Pulled By: mrambacher

fbshipit-source-id: 6b45de3f300750c79f751f6227dece9cfd44085d
2021-09-29 04:04:40 -07:00
Levi Tamasi be206db351 Deflake MySQLStyleTransactionTest.TransactionStressTest in "status checked" mode (#8947)
Summary:
There is a corner case when using WriteUnprepared transactions when
`WriteUnpreparedTxn::Get` returns `Status::TryAgain` instead of
propagating the result of `GetFromBatchAndDB`. The patch adds
`PermitUncheckedError` to make the `ASSERT_STATUS_CHECKED` build pass in
this case as well.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8947

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D31125422

Pulled By: ltamasi

fbshipit-source-id: 42de51dcfa9384e032244c2b4d3f40e9a4111194
2021-09-22 16:40:25 -07:00
Peter Dillinger 4750421ece Replace most typedef with using= (#8751)
Summary:
Old typedef syntax is confusing

Most but not all changes with

    perl -pi -e 's/typedef (.*) ([a-zA-Z0-9_]+);/using $2 = $1;/g' list_of_files
    make format

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8751

Test Plan: existing

Reviewed By: zhichao-cao

Differential Revision: D30745277

Pulled By: pdillinger

fbshipit-source-id: 6f65f0631c3563382d43347896020413cc2366d9
2021-09-07 11:31:59 -07:00
Yanqin Jin 2b367fa8cc Fix bug caused by releasing snapshot(s) during compaction (#8608)
Summary:
In debug mode, we are seeing assertion failure as follows

```
db/compaction/compaction_iterator.cc:980: void rocksdb::CompactionIterator::PrepareOutput(): \
Assertion `ikey_.type != kTypeDeletion && ikey_.type != kTypeSingleDeletion' failed.
```

It is caused by releasing earliest snapshot during compaction between the execution of
`NextFromInput()` and `PrepareOutput()`.

In one case, as demonstrated in unit test `WritePreparedTransaction.ReleaseEarliestSnapshotDuringCompaction_WithSD2`,
incorrect result may be returned by a following range scan if we disable assertion, as in opt compilation
level: the SingleDelete marker's sequence number is zeroed out, but the preceding PUT is also
outputted to the SST file after compaction. Due to the logic of DBIter, the PUT will not be
skipped and will be returned by iterator in range scan. https://github.com/facebook/rocksdb/issues/8661 illustrates what happened.

Fix by taking a more conservative approach: make compaction zero out sequence number only
if key is in the earliest snapshot when the compaction starts.

Another assertion failure is
```
Assertion `current_user_key_snapshot_ == last_snapshot' failed.
```

It's caused by releasing the snapshot between the PUT and SingleDelete during compaction.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8608

Test Plan: make check

Reviewed By: jay-zhuang

Differential Revision: D30145645

Pulled By: riversand963

fbshipit-source-id: 699f58e66faf70732ad53810ccef43935d3bbe81
2021-08-17 22:14:20 -07:00
Yanqin Jin 066b51126d Several simple local code clean-ups (#8565)
Summary:
This PR tries to remove some unnecessary checks as well as unreachable code blocks to
improve readability. An obvious non-public API method naming typo is also corrected.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8565

Test Plan: make check

Reviewed By: lth

Differential Revision: D29963984

Pulled By: riversand963

fbshipit-source-id: cc96e8f09890e5cfe9b20eadb63bdca5484c150a
2021-07-30 12:07:49 -07:00
mrambacher 3aee4fbd41 Make EventListener into a Customizable Class (#8473)
Summary:
- Added Type/CreateFromString
- Added ability to load EventListeners to DBOptions
- Since EventListeners did not previously have a Name(), defaulted to "".  If there is no name, the listener cannot be loaded from the ObjectRegistry.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8473

Reviewed By: zhichao-cao

Differential Revision: D29901488

Pulled By: mrambacher

fbshipit-source-id: 2d3a4aa6db1562ac03e7ad41b360e3521d486254
2021-07-27 07:47:02 -07:00
longlijian 4e4ec16957 Replace the namespace "rocksdb" to "ROCKSDB_NAMESPACE" (#8531)
Summary:
For more detail can reference the https://github.com/facebook/rocksdb/issues/6433
(https://github.com/facebook/rocksdb/pull/6433)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8531

Reviewed By: siying

Differential Revision: D29717057

Pulled By: ajkr

fbshipit-source-id: 3ccad9501e5612590e54a7cf8c447118f323c7f4
2021-07-15 17:23:39 -07:00
Andrew Kryczka ed8eb436db Move slow valgrind tests behind -DROCKSDB_FULL_VALGRIND_RUN (#8475)
Summary:
Various tests had disabled valgrind due to it slowing down and timing
out (as is the case right now) the CI runs. Where a test was disabled with no comment,
I assumed slowness was the cause. For these tests that were slow under
valgrind, as well as the ones identified in https://github.com/facebook/rocksdb/issues/8352, this PR moves them
behind the compiler flag `-DROCKSDB_FULL_VALGRIND_RUN`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8475

Test Plan: running `make full_valgrind_test`, `make valgrind_test`, `make check`; will verify they appear working correctly

Reviewed By: jay-zhuang

Differential Revision: D29504843

Pulled By: ajkr

fbshipit-source-id: 2aac90749cfbd30d5ce11cb29a07a1b9314eeea7
2021-07-07 11:14:05 -07:00
Jay Zhuang f89423a57a Revert "Revert "Snapshot release triggered compaction without multiple tombstones (#8357)" (#8410)" (#8438)
Summary:
This reverts commit 25be1ed66a.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8438

Test Plan: Run the impacted mysql test 40 times

Reviewed By: ajkr

Differential Revision: D29286247

Pulled By: jay-zhuang

fbshipit-source-id: d3bd056971a19a8b012d5d0295fa045c012b3c04
2021-06-22 11:10:03 -07:00
Andrew Kryczka 25be1ed66a Revert "Snapshot release triggered compaction without multiple tombstones (#8357)" (#8410)
Summary:
This reverts commit 9167ece586.

It was found to reliably trip a compaction picking conflict assertion in a MyRocks unit test. We don't understand why yet so reverting in the meantime.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8410

Test Plan: `make check -j48`

Reviewed By: jay-zhuang

Differential Revision: D29150300

Pulled By: ajkr

fbshipit-source-id: 2de8664f355d6da015e84e5fec2e3f90f49741c8
2021-06-15 18:15:15 -07:00
Andrew Kryczka 9167ece586 Snapshot release triggered compaction without multiple tombstones (#8357)
Summary:
This is a duplicate of https://github.com/facebook/rocksdb/issues/4948 by mzhaom to fix tests after rebase.

This change is a follow-up to https://github.com/facebook/rocksdb/issues/4927, which made this possible by allowing tombstone dropping/seqnum zeroing optimizations on the last key in the compaction. Now the `largest_seqno != 0` condition suffices to prevent snapshot release triggered compaction from entering an infinite loop.

The issues caused by the extraneous condition `level_and_file.second->num_deletions > 1` are:

- files could have `largest_seqno > 0` forever making it impossible to tell they cannot contain any covering keys
- it doesn't trigger compaction when there are many overwritten keys. Some MyRocks use case actually doesn't use Delete but instead calls Put with empty value to "delete" keys, so we'd like to be able to trigger compaction in this case too.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8357

Test Plan: - make check

Reviewed By: jay-zhuang

Differential Revision: D28855340

Pulled By: ajkr

fbshipit-source-id: a261b51eecafec492499e6d01e8e43112f801798
2021-06-04 00:21:40 -07:00
Andrew Kryczka d76c46e6a0 Deflake TransactionStressTest.ExpiredTransactionDataRace1 (#8258)
Summary:
We saw the `Commit()` fail with "Operation expired" so apparently the
expiration time is too short. Increased the magnitude of the times in
this test to make flakiness less likely.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8258

Reviewed By: jay-zhuang

Differential Revision: D28177033

Pulled By: ajkr

fbshipit-source-id: 0357acee6cc14c104b6ccd39231a683a606ab130
2021-05-12 15:49:05 -07:00