Summary:
This PR is based on nbronson's diff with small
modifications to wire it up with existing interface. Comparing to
previous version, this approach works better for inserting keys in
decreasing order or updating the same key, and impose less restriction
to the prefix extractor.
---- Summary from original diff ----
This diff introduces a single InlineSkipList::Insert that unifies
the existing sequential insert optimization (prev_), concurrent insertion,
and insertion using externally-managed insertion point hints.
There's a deep symmetry between insertion hints (cursors) and the
concurrent algorithm. In both cases we have partial information from
the recent past that is likely but not certain to be accurate. This diff
introduces the struct InlineSkipList::Splice, which encodes predecessor
and successor information in the same form that was previously only used
within a single call to InsertConcurrently. Splice holds information
about an insertion point that can be used to levera
Closes https://github.com/facebook/rocksdb/pull/1561
Differential Revision: D4217283
Pulled By: yiwu-arbug
fbshipit-source-id: 33ee437
Summary:
Currently our skip-list have an optimization to speedup sequential
inserts from a single stream, by remembering the last insert position.
We extend the idea to support sequential inserts from multiple streams,
and even tolerate small reordering wihtin each stream.
This PR is the interface part adding the following:
- Add `memtable_insert_prefix_extractor` to allow specifying prefix for each key.
- Add `InsertWithHint()` interface to memtable, to allow underlying
implementation to return a hint of insert position, which can be later
pass back to optimize inserts.
- Memtable will maintain a map from prefix to hints and pass the hint
via `InsertWithHint()` if `memtable_insert_prefix_extractor` is non-null.
Closes https://github.com/facebook/rocksdb/pull/1419
Differential Revision: D4079367
Pulled By: yiwu-arbug
fbshipit-source-id: 3555326
Summary:
Add new Iterator API, `SeekForPrev`: find the last key that <= target key
support prefix_extractor
support prefix_same_as_start
support upper_bound
not supported in iterators without Prev()
Also add tests in db_iter_test and db_iterator_test
Pass all tests
Cheers!
Test Plan: make all check -j64
Reviewers: andrewkr, yiwu, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D64149
Summary: If users turn on concurrent insert but the memtable doesn't support it, they might see unexcepted crash. Fix it by explicitly fail.
Test Plan:
Run different setting of stress_test and make sure it fails correctly.
Will add a unit test too.
Reviewers: anthony, kradhakrishnan, IslamAbdelRahman, yhchiang, andrewkr, ngbronson
Reviewed By: ngbronson
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D53895
