Summary:
Currently non-2pc writes do the 2nd dummy write to actually commit the transaction. This was necessary to ensure that publishing the commit sequence number will be done only from one queue (the queue that does not write to memtable). This is however not necessary when we have only one write queue, which is actually the setup that would be used by non-2pc writes. This patch eliminates the 2nd write when two_write_queues are disabled by updating the commit map in the 1st write.
Closes https://github.com/facebook/rocksdb/pull/3277
Differential Revision: D6575392
Pulled By: maysamyabandeh
fbshipit-source-id: 8ab458f7ca506905962f9166026b2ec81e749c46
Summary:
Add PreReleaseCallback to be called at the end of WriteImpl but before publishing the sequence number. The callback is used in WritePrepareTxn to i) update the commit map, ii) update the last published sequence number in the 2nd write queue. It also ensures that all the commits will go to the 2nd queue.
These changes will ensure that the commit map is updated before the sequence number is published and used by reading snapshots. If we use two write queues, the snapshots will use the seq number published by the 2nd queue. If we use one write queue (the default, the snapshots will use the last seq number in the memtable, which also indicates the last published seq number.
Closes https://github.com/facebook/rocksdb/pull/3205
Differential Revision: D6438959
Pulled By: maysamyabandeh
fbshipit-source-id: f8b6c434e94bc5f5ab9cb696879d4c23e2577ab9
Summary:
This patch implements MultiGet API for WritePreparedTxnDB and update the existing unit tests.
Closes https://github.com/facebook/rocksdb/pull/3196
Differential Revision: D6401493
Pulled By: maysamyabandeh
fbshipit-source-id: 51501a1e32645fc2da8680e77a50035f6530f2cc
Summary:
The sequence number was not properly advanced after a rollback marker. The patch extends the existing unit tests to detect the bug and also fixes it.
Closes https://github.com/facebook/rocksdb/pull/3157
Differential Revision: D6304291
Pulled By: maysamyabandeh
fbshipit-source-id: 1b519c44a5371b802da49c9e32bd00087a8da401
Summary:
Add tests to ensure that WritePrepared and WriteCommitted policies are cross compatible when the db WAL is empty. This is important when the admin want to switch between the policies. In such case, before the switch the admin needs to empty the WAL by i) committing/rollbacking all the pending transactions, ii) FlushMemTables
Closes https://github.com/facebook/rocksdb/pull/3118
Differential Revision: D6227247
Pulled By: maysamyabandeh
fbshipit-source-id: bcde3d92c1e89cda3b9cfa69f6a20af5d8993db7
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
Summary:
A few simple changes to allow RocksDB to be built on OpenBSD. Let me know if any further changes are needed.
Closes https://github.com/facebook/rocksdb/pull/3061
Differential Revision: D6138800
Pulled By: ajkr
fbshipit-source-id: a13a17b5dc051e6518bd56a8c5efd1d24dd81b0c
Summary:
Enable concurrent_prepare flag for WritePrepared transactions and extend the existing transaction tests with this config.
Closes https://github.com/facebook/rocksdb/pull/3046
Differential Revision: D6106534
Pulled By: maysamyabandeh
fbshipit-source-id: 88c8d21d45bc492beb0a131caea84a2ac5e7d38c
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
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
Summary:
Compaction will output keys with sequence number 0, if it is visible to
earliest snapshot. Adding a test to make sure IsInSnapshot() report sequence number 0 is
visible to any snapshot.
Closes https://github.com/facebook/rocksdb/pull/2974
Differential Revision: D5990665
Pulled By: yiwu-arbug
fbshipit-source-id: ef50ebc777ff8ca688771f3ab598c7a609b0b65e
Summary:
With WriteCommitted, when the write batch has duplicate keys, the txn db simply inserts them to the db with different seq numbers and let the db ignore/merge the duplicate values at the read time. With WritePrepared all the entries of the batch are inserted with the same seq number which prevents us from benefiting from this simple solution.
This patch applies a hackish solution to unblock the end-to-end testing. The hack is to be replaced with a proper solution soon. The patch simply detects the duplicate key insertions, and mark the previous one as obsolete. Then before writing to the db it rewrites the batch eliminating the obsolete keys. This would incur a memcpy cost. Furthermore handing duplicate merge would require to do FullMerge instead of simply ignoring the previous value, which is not handled by this patch.
Closes https://github.com/facebook/rocksdb/pull/2969
Differential Revision: D5976337
Pulled By: maysamyabandeh
fbshipit-source-id: 114e65b66f137d8454ff2d1d782b8c05da95f989
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
Summary:
Recover txns from the WAL. Also added some unit tests.
Closes https://github.com/facebook/rocksdb/pull/2901
Differential Revision: D5859596
Pulled By: maysamyabandeh
fbshipit-source-id: 6424967b231388093b4effffe0a3b1b7ec8caeb0
Summary:
By default the seq number in DB is increased once per written key. WritePrepared txns requires the seq to be increased once per the entire batch so that the seq would be used as the prepare timestamp by which the transaction is identified. Also we need to increase seq for the commit marker since it would give a unique id to the commit timestamp of transactions.
Two unit tests are added to verify our understanding of how the seq should be increased. The recovery path requires much more work and is left to another patch.
Closes https://github.com/facebook/rocksdb/pull/2885
Differential Revision: D5837843
Pulled By: maysamyabandeh
fbshipit-source-id: a08960b93d727e1cf438c254d0c2636fb133cc1c
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
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
Summary:
The patch skips write_prepared_transaction_test from travis as they time out there. They are still covered in daily runs of tests.
Closes https://github.com/facebook/rocksdb/pull/2836
Differential Revision: D5767203
Pulled By: maysamyabandeh
fbshipit-source-id: 51045ef98a745197136e14b2ec02fc6f38081b75
Summary:
Add -DPORTABLE=1
port::cacheline_aligned_alloc() has arguments swapped which prevents every single test from running.
Closes https://github.com/facebook/rocksdb/pull/2815
Differential Revision: D5751661
Pulled By: siying
fbshipit-source-id: e0857d6e138ec46035b3c23d7c3c751901a0a4a0
Maysam Yabandeh