Commit Graph

27 Commits

Author SHA1 Message Date
Maysam Yabandeh
537a233941 Exclude StackableDB from transaction stress tests (#4132)
Summary:
The transactions are currently tested with and without using StackableDB. This is mostly to check that the code path is consistent with stackable db as well. Slow, stress tests however do not benefit from being run again with StackableDB. The patch excludes StackableDB from such tests.
On a single core it reduced the runtime of transaction_test from 199s to 135s.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4132

Differential Revision: D8841655

Pulled By: maysamyabandeh

fbshipit-source-id: 7b9aaba2673b542b195439dfb306cef26bd63b19
2018-07-13 13:59:11 -07:00
Manuel Ung
b9846370e9 WriteUnPrepared: Add support for recovering WriteUnprepared transactions (#4078)
Summary:
This adds support for recovering WriteUnprepared transactions through the following changes:
- The information in `RecoveredTransaction` is extended so that it can reference multiple batches.
- `MarkBeginPrepare` is extended with a bool indicating whether it is an unprepared begin, and this is passed down to `InsertRecoveredTransaction` to indicate whether the current transaction is prepared or not.
- `WriteUnpreparedTxnDB::Initialize` is overridden so that it will rollback unprepared transactions from the recovered transactions. This can be done without updating the prepare heap/commit map, because this is before the DB has finished initializing, and after writing the rollback batch, those data structures should not contain information about the rolled back transaction anyway.

Commit/Rollback of live transactions is still unimplemented and will come later.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4078

Differential Revision: D8703382

Pulled By: lth

fbshipit-source-id: 7e0aada6c23bd39299f1f20d6c060492e0e6b60a
2018-07-06 17:59:13 -07:00
Maysam Yabandeh
cfb86659bf WritePrepared Txn: enable rollback in stress test
Summary:
Rollback was disabled in stress test since there was a concurrency issue in WritePrepared rollback algorithm. The issue is fixed by caching the column family handles in WritePrepared to skip getting them from the db when needed for rollback.

Tested by running transaction stress test under tsan.
Closes https://github.com/facebook/rocksdb/pull/3785

Differential Revision: D7793727

Pulled By: maysamyabandeh

fbshipit-source-id: d81ab6fda0e53186ca69944cfe0712ce4869451e
2018-05-02 18:13:05 -07:00
Maysam Yabandeh
b225de7e10 WritePrepared Txn: smallest_prepare optimization
Summary:
The is an optimization to reduce lookup in the CommitCache when querying IsInSnapshot. The optimization takes the smallest uncommitted data at the time that the snapshot was taken and if the sequence number of the read data is lower than that number it assumes the data as committed.
To implement this optimization two changes are required: i) The AddPrepared function must be called sequentially to avoid out of order insertion in the PrepareHeap (otherwise the top of the heap does not indicate the smallest prepare in future too), ii) non-2PC transactions also call AddPrepared if they do not commit in one step.
Closes https://github.com/facebook/rocksdb/pull/3649

Differential Revision: D7388630

Pulled By: maysamyabandeh

fbshipit-source-id: b79506238c17467d590763582960d4d90181c600
2018-04-02 20:27:41 -07:00
Maysam Yabandeh
680864ae54 WritePrepared Txn: Fix bug with duplicate keys during recovery
Summary:
Fix the following bugs:
- During recovery a duplicate key was inserted twice into the write batch of the recovery transaction,
once when the memtable returns false (because it was duplicates) and once for the 2nd attempt. This would result into different SubBatch count measured when the recovered transactions is committing.
- If a cf is flushed during recovery the memtable is not available to assist in detecting the duplicate key. This could result into not advancing the sequence number when iterating over duplicate keys of a flushed cf and hence inserting the next key with the wrong sequence number.
- SubBacthCounter would reset the comparator to default comparator after the first duplicate key. The 2nd duplicate key hence would have gone through a wrong comparator and not being detected.
Closes https://github.com/facebook/rocksdb/pull/3562

Differential Revision: D7149440

Pulled By: maysamyabandeh

fbshipit-source-id: 91ec317b165f363f5d11ff8b8c47c81cebb8ed77
2018-03-05 10:57:59 -08:00
Maysam Yabandeh
828211e901 WritePrepared Txn: fix non-emptied PreparedHeap bug
Summary:
Under a certain sequence of accessing PreparedHeap, there was a bug that would not successfully empty the heap. This would result in performance issues when the heap content is moved to old_prepared_ after max_evicted_seq_ advances the orphan prepared sequence numbers. The patch fixed the bug and add more unit tests. It also does more logging when the unlikely scenarios are faced
Closes https://github.com/facebook/rocksdb/pull/3526

Differential Revision: D7038486

Pulled By: maysamyabandeh

fbshipit-source-id: f1e40bea558f67b03d2a29131fcb8734c65fce97
2018-02-21 13:42:23 -08:00
Maysam Yabandeh
c178da053b WritePrepared Txn: optimizations for sysbench update_noindex
Summary:
These are optimization that we applied to improve sysbech's update_noindex performance.
1. Make use of LIKELY compiler hint
2. Move std::atomic so the subclass
3. Make use of skip_prepared in non-2pc transactions.
Closes https://github.com/facebook/rocksdb/pull/3512

Differential Revision: D7000075

Pulled By: maysamyabandeh

fbshipit-source-id: 1ab8292584df1f6305a4992973fb1b7933632181
2018-02-16 08:42:31 -08:00
Maysam Yabandeh
8feee28020 Add skip_cc option to TransactionDB::Write
Summary:
Compared to DB::Write, TransactionDB::Write has the additional overhead of creating and initializing an internal transaction object, as well as the overhead of locking/unlocking the keys. This patch extends the TransactionDB::Write with an skip_cc option to allow the users to indicate that the write batch do not conflict with others and the concurrency control and its overhead can be skipped. TransactionDB::Write by default calls DB::Write when skip_cc is set, which works for WriteCommitted WritePolicy. Any other flavor of TransactionDB that is not compatible with this default behavior (such as WritePreparedTxnDB) can extend ::Write and implement their own approach for taking into account the skip_cc optimization.
Closes https://github.com/facebook/rocksdb/pull/3457

Differential Revision: D6877318

Pulled By: maysamyabandeh

fbshipit-source-id: 56f4e21db87ff71492db4e376fb7c2b03dfeab6b
2018-02-06 15:28:24 -08:00
Maysam Yabandeh
88d8b2a2f5 WritePrepared Txn: Duplicate Keys, Txn Part
Summary:
This patch takes advantage of memtable being able to detect duplicate <key,seq> and returning TryAgain to handle duplicate keys in WritePrepared Txns. Through WriteBatchWithIndex's index it detects existence of at least a duplicate key in the write batch. If duplicate key was reported, it then pays the cost of counting the number of sub-patches by iterating over the write batch and pass it to DBImpl::Write. DB will make use of the provided batch_count to assign proper sequence numbers before sending them to the WAL. When later inserting the batch to the memtable, it increases the seq each time memtbale reports a duplicate (a sub-patch in our counting) and tries again.
Closes https://github.com/facebook/rocksdb/pull/3455

Differential Revision: D6873699

Pulled By: maysamyabandeh

fbshipit-source-id: db8487526c3a5dc1ddda0ea49f0f979b26ae648d
2018-02-05 18:43:24 -08:00
Maysam Yabandeh
60d83df23d WritePrepared Txn: Move DB class to its own file
Summary:
Move  WritePreparedTxnDB from pessimistic_transaction_db.h to its own header, write_prepared_txn_db.h
Closes https://github.com/facebook/rocksdb/pull/3114

Differential Revision: D6220987

Pulled By: maysamyabandeh

fbshipit-source-id: 18893fb4fdc6b809fe117dabb544080f9b4a301b
2017-11-02 11:14:30 -07:00
Maysam Yabandeh
17731a43a6 WritePrepared Txn: Optimize for recoverable state
Summary:
GetCommitTimeWriteBatch is currently used to store some state as part of commit in 2PC. In MyRocks it is specifically used to store some data that would be needed only during recovery. So it is not need to be stored in memtable right after each commit.
This patch enables an optimization to write the GetCommitTimeWriteBatch only to the WAL. The batch will be written to memtable during recovery when the WAL is replayed. To cover the case when WAL is deleted after memtable flush, the batch is also buffered and written to memtable right before each memtable flush.
Closes https://github.com/facebook/rocksdb/pull/3071

Differential Revision: D6148023

Pulled By: maysamyabandeh

fbshipit-source-id: 2d09bae5565abe2017c0327421010d5c0d55eaa7
2017-11-01 17:26:46 -07:00
Yi Wu
8c392a31d7 WritePrepared Txn: Iterator
Summary:
On iterator create, take a snapshot, create a ReadCallback and pass the ReadCallback to the underlying DBIter to check if key is committed.
Closes https://github.com/facebook/rocksdb/pull/2981

Differential Revision: D6001471

Pulled By: yiwu-arbug

fbshipit-source-id: 3565c4cdaf25370ba47008b0e0cb65b31dfe79fe
2017-10-09 17:15:28 -07:00
Yi Wu
17c6325e8a WritePrepare Txn: Cancel flush/compaction before destruction
Summary:
On WritePreparedTxnDB destruct there could be running compaction/flush holding a SnapshotChecker, which holds a pointer back to WritePreparedTxnDB. Make sure those jobs finished before destructing WritePreparedTxnDB.

This is caught by TransactionTest::SeqAdvanceTest.
Closes https://github.com/facebook/rocksdb/pull/2982

Differential Revision: D6002957

Pulled By: yiwu-arbug

fbshipit-source-id: f1e70390c9798d1bd7959f5c8e2a1c14100773c3
2017-10-06 20:55:53 -07:00
Yi Wu
d1b74b0c82 WritePrepared Txn: Compaction/Flush
Summary:
Update Compaction/Flush to support WritePreparedTxnDB: Add SnapshotChecker which is a proxy to query WritePreparedTxnDB::IsInSnapshot. Pass SnapshotChecker to DBImpl on WritePreparedTxnDB open. CompactionIterator use it to check if a key has been committed and if it is visible to a snapshot. In CompactionIterator:
* check if key has been committed. If not, output uncommitted keys AS-IS.
* use SnapshotChecker to check if key is visible to a snapshot when in need.
* do not output key with seq = 0 if the key is not committed.
Closes https://github.com/facebook/rocksdb/pull/2926

Differential Revision: D5902907

Pulled By: yiwu-arbug

fbshipit-source-id: 945e037fdf0aa652dc5ba0ad879461040baa0320
2017-10-06 10:41:53 -07:00
Maysam Yabandeh
d27258d3a6 WritePrepared Txn: Rollback
Summary:
Implement the rollback of WritePrepared txns. For each modified value, it reads the value before the txn and write it back. This would cancel out the effect of transaction. It also remove the rolled back txn from prepared heap.
Closes https://github.com/facebook/rocksdb/pull/2946

Differential Revision: D5937575

Pulled By: maysamyabandeh

fbshipit-source-id: a6d3c47f44db3729f44b287a80f97d08dc4e888d
2017-10-02 19:59:27 -07:00
Maysam Yabandeh
385049baf2 WritePrepared Txn: Recovery
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
2017-09-28 16:56:45 -07:00
Yi Wu
ec48e5c77f Add TransactionDB::SingleDelete()
Summary:
Looks like the API is simply missing. Adding it.
Closes https://github.com/facebook/rocksdb/pull/2937

Differential Revision: D5919955

Pulled By: yiwu-arbug

fbshipit-source-id: 6e2e9c96c29882b0bb4113d1f8efb72bffc57878
2017-09-27 10:27:26 -07:00
Maysam Yabandeh
09713a64b3 WritePrepared Txn: Lock-free CommitMap
Summary:
We had two proposals for lock-free commit maps. This patch implements the latter one that was simpler. We can later experiment with both proposals.

In this impl each entry is an std::atomic of uint64_t, which are accessed via memory_order_acquire/release. In x86_64 arch this is compiled to simple reads and writes from memory.
Closes https://github.com/facebook/rocksdb/pull/2861

Differential Revision: D5800724

Pulled By: maysamyabandeh

fbshipit-source-id: 41abae9a4a5df050a8eb696c43de11c2770afdda
2017-09-13 12:12:11 -07:00
Maysam Yabandeh
f46464d383 write-prepared txn: call IsInSnapshot
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
2017-09-11 09:14:48 -07:00
Maysam Yabandeh
fce6c892ab Advance max evicted seq in coarser granularity
Summary:
This patch advances the max_evicted_seq_ is larger granularities to reduce the overhead of updating the relevant data structures.

It also refactor the related code and adds testing to that. As part of this patch some of the TODOs for removing usage of non-static const members are also addressed.
Closes https://github.com/facebook/rocksdb/pull/2844

Differential Revision: D5772928

Pulled By: maysamyabandeh

fbshipit-source-id: f4fcc2948be69c034f10812cf922ce5ab82ef98c
2017-09-08 14:41:22 -07:00
Maysam Yabandeh
26ac24f199 Add more unit test to write_prepared txns
Summary: Closes https://github.com/facebook/rocksdb/pull/2798

Differential Revision: D5724173

Pulled By: maysamyabandeh

fbshipit-source-id: fb6b782d933fb4be315b1a231a6a67a66fdc9c96
2017-08-31 09:41:27 -07:00
Maysam Yabandeh
fbfa3e7a43 WriteAtPrepare: Efficient read from snapshot list
Summary:
Divide the old snapshots to two lists: a few that fit into a cached array and the rest in a vector, which is expected to be empty in normal cases. The former is to optimize concurrent reads from snapshots without requiring locks. It is done by an array of std::atomic, from which std::memory_order_acquire reads are compiled to simple read instructions in most of the x86_64 architectures.
Closes https://github.com/facebook/rocksdb/pull/2758

Differential Revision: D5660504

Pulled By: maysamyabandeh

fbshipit-source-id: 524fcf9a8e7f90a92324536456912a99aaa6740c
2017-08-26 01:00:38 -07:00
Maysam Yabandeh
cd26af3476 Add unit test for WritePrepared skeleton
Summary: Closes https://github.com/facebook/rocksdb/pull/2756

Differential Revision: D5660516

Pulled By: maysamyabandeh

fbshipit-source-id: f3f3d3b5f544007a7fbdd78e49e4738b4437c7ee
2017-08-23 13:56:03 -07:00
Archit Mishra
bddd5d3630 Added mechanism to track deadlock chain
Summary:
Changes:
* extended the wait_txn_map to track additional information
* designed circular buffer to store n latest deadlocks' information
* added test coverage to verify the additional information tracked is accurately stored in the buffer
Closes https://github.com/facebook/rocksdb/pull/2630

Differential Revision: D5478025

Pulled By: armishra

fbshipit-source-id: 2b138de7b5a73f5ca554fc3ff8220a3be49f39e7
2017-08-17 18:56:21 -07:00
Maysam Yabandeh
eb6425303e Update WritePrepared with the pseudo code
Summary:
Implement the main body of WritePrepared pseudo code. This includes PrepareInternal and CommitInternal, as well as AddCommitted which updates the commit map. It also provides a IsInSnapshot method that could be later called form the read path to decide if a version is in the read snapshot or it should other be skipped.

This patch lacks unit tests and does not attempt to offer an efficient implementation. The idea is that to have the API specified so that we can work on related tasks in parallel.
Closes https://github.com/facebook/rocksdb/pull/2713

Differential Revision: D5640021

Pulled By: maysamyabandeh

fbshipit-source-id: bfa7a05e8d8498811fab714ce4b9c21530514e1c
2017-08-16 16:57:47 -07:00
Maysam Yabandeh
bdc056f8aa Refactor PessimisticTransaction
Summary:
This patch splits Commit and Prepare into lock-related logic and db-write-related logic. It moves lock-related logic to PessimisticTransaction to be reused by all children classes and movies the existing impl of db-write-related to PrepareInternal, CommitSingleInternal, and CommitInternal in WriteCommittedTxnImpl.
Closes https://github.com/facebook/rocksdb/pull/2691

Differential Revision: D5569464

Pulled By: maysamyabandeh

fbshipit-source-id: d1b8698e69801a4126c7bc211745d05c636f5325
2017-08-07 16:12:29 -07:00
Maysam Yabandeh
c9804e007a Refactor TransactionDBImpl
Summary:
This opens space for the new implementations of TransactionDBImpl such as WritePreparedTxnDBImpl that has a different policy of how to write to DB.
Closes https://github.com/facebook/rocksdb/pull/2689

Differential Revision: D5568918

Pulled By: maysamyabandeh

fbshipit-source-id: f7eac866e175daf3793ae79da108f65cc7dc7b25
2017-08-05 17:26:15 -07:00