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: Closes https://github.com/facebook/rocksdb/pull/1488

Differential Revision: D4157784

Pulled By: siying

fbshipit-source-id: f150081

Summary:
Add avoid_flush_during_shutdown DB option.
Closes https://github.com/facebook/rocksdb/pull/1451

Differential Revision: D4108643

Pulled By: yiwu-arbug

fbshipit-source-id: abdaf4d

Summary: Closes https://github.com/facebook/rocksdb/pull/1427

Differential Revision: D4094732

Pulled By: yiwu-arbug

fbshipit-source-id: b9b79e9

Summary:
Bump RocksDB version to 4.13

Test Plan:
unit tests

Reviewers: sdong, IslamAbdelRahman, andrewkr, lightmark

Subscribers: leveldb

Summary: update new feature in history and avoid breaking mongorocks

Test Plan: make check

Reviewers: sdong, yiwu, andrewkr

Reviewed By: andrewkr

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D64611

Summary:
Add DB::SetDBOptions to dynamic change max_background_compactions and base_background_compactions.
I'll add more dynamic changeable options soon.

Test Plan: unit test.

Reviewers: yhchiang, IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D64749

Summary: A convience method to atomically get and reset ticker count. I'm wanting to use it to have a thin wrapper to the statistics object to export ticker counts to ODS for LogDevice (since they don't even use fb303).

Test Plan:
test in LogDevice shadow cluster.
https://fburl.com/461868822

Reviewers: andrewkr, yhchiang, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D64869

Summary: DB::GetOptions() reflect dynamic changed options.

Test Plan: See the new unit test.

Reviewers: yhchiang, sdong, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D63903

Summary: Release 4.12

Test Plan: none

Reviewers: andrewkr, yiwu, lightmark, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D63885

Summary: as titled

Test Plan: doitlive

Reviewers: sdong, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D63777

Summary:
ZSTD 1.0.0 is coming. We can finally add a support of ZSTD without worrying about compatibility.
Still keep ZSTDNotFinal for compatibility reason.

Test Plan: Run all tests. Run db_bench with ZSTD version with RocksDB built with ZSTD 1.0 and older.

Reviewers: andrewkr, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: cyan, igor, IslamAbdelRahman, leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D63141

Summary: There's no reference to ImmutableCFOptions elsewhere in /include/rocksdb. ImmutableCFOptions was introduced in this commit (https://github.com/facebook/rocksdb/commit/5665e5e285c25c1674567f747df92c131037d2dc) but later its reference in /include/rocksdb/table.h is removed.

Test Plan:
  make all check

Reviewers: IslamAbdelRahman, sdong, yhchiang

Reviewed By: yhchiang

Subscribers: yhchiang, andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D63177

Merge options source_compaction_factor, max_grandparent_overlap_bytes and expanded_compaction_factor into max_compaction_bytes

Summary: To reduce number of options, merge source_compaction_factor, max_grandparent_overlap_bytes and expanded_compaction_factor into max_compaction_bytes.

Test Plan: Add two new unit tests. Run all existing tests, including jtest.

Reviewers: yhchiang, igor, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59829

Summary:
Update History.md to reflect recent change that ensures unpersisted data
is flushed even if clients call CancelAllBackgroundWork() directly.

Test Plan: Review rendering of markdown.

Reviewers: sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D62703

Summary:
Clock-based cache implemenetation aim to have better concurreny than
default LRU cache. See inline comments for implementation details.

Test Plan:
Update cache_test to run on both LRUCache and ClockCache. Adding some
new tests to catch some of the bugs that I fixed while implementing the
cache.

Reviewers: kradhakrishnan, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D61647

Summary:
Need to change HISTORY.md for 4.11.
4.10 was not updated either. Update it together.

Test Plan: Not needed.

Reviewers: kradhakrishnan, andrewkr, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D61665

Summary: Add a utility function that trigger necessary full compaction and put output to the correct level by looking at new options and old options.

Test Plan: Add unit tests for it.

Reviewers: andrewkr, igor, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: muthu, sumeet, leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D60783

Change options memtable_prefix_bloom_huge_page_tlb_size => memtable_huge_page_size and cover huge page to memtable too

Summary: Extend the option memtable_prefix_bloom_huge_page_tlb_size from just putting memtable bloom filter to huge page to memtable itself too.

Test Plan: Run all existing tests.

Reviewers: IslamAbdelRahman, yhchiang, andrewkr

Reviewed By: andrewkr

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D60513

Summary: Add option write_buffer_manager to help users control total memory spent on memtables across multiple DB instances.

Test Plan: Add a new unit test.

Reviewers: yhchiang, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: adela, benj, sumeet, muthu, leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59925

Summary: We saw instances where total_log_size is off the real value, but I'm not able to reproduce it. Add more logging to help debugging when it happens again.

Test Plan: Run the unit test and see the logging.

Reviewers: andrewkr, yhchiang, igor, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D60081

Summary:
This diff uses the CF ID and CF name properties in the SST file
to associate recovered data with the proper column family. Depends on D59775.

- In ScanTable(), create column families in VersionSet each time a new one is discovered (via reading SST file properties)
- In ConvertLogToTable(), dump an SST file for every column family with data in the WAL
- In AddTables(), make a VersionEdit per-column family that adds all of that CF's tables

Test Plan:
  $ ./repair_test

Reviewers: yhchiang, IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D59781

Summary:
Add a read option `background_purge_on_iterator_cleanup` to avoid deleting files in foreground when destroying iterators.
Instead, a job is scheduled in high priority queue and would be executed in a separate background thread.

Test Plan: Add a variant of PurgeObsoleteFileTest. Turn on background purge option in the new test, and use sleeping task to ensure files are deleted in background.

Reviewers: IslamAbdelRahman, sdong

Reviewed By: IslamAbdelRahman

Subscribers: andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59499

Summary: filter_deltes is not a frequently used feature. Remove it.

Test Plan: Run all test suites.

Reviewers: igor, yhchiang, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59427

Summary: char is not signed in some platforms. Having negative values confuse those compilers.

Test Plan: Run all existing tests.

Reviewers: andrewkr, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59619

Summary:
Add option to not flush memtable on open()
In case the option is enabled, don't delete existing log files by not updating log numbers to MANIFEST.
Will still flush if we need to (e.g. memtable full in the middle). In that case we also flush final memtable.
If wal_recovery_mode = kPointInTimeRecovery, do not halt immediately after encounter corruption. Instead, check if seq id of next log file is last_log_sequence + 1. In that case we continue recovery.

Test Plan: See unit test.

Reviewers: dhruba, horuff, sdong

Reviewed By: sdong

Subscribers: benj, yhchiang, andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D57813

memtable_prefix_bloom_bits -> memtable_prefix_bloom_bits_ratio and deprecate memtable_prefix_bloom_probes

Summary:
memtable_prefix_bloom_probes is not a critical option. Remove it to reduce number of options.
It's easier for users to make mistakes with memtable_prefix_bloom_bits, turn it to memtable_prefix_bloom_bits_ratio

Test Plan: Run all existing tests

Reviewers: yhchiang, igor, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: gunnarku, yoshinorim, MarkCallaghan, leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59199

Summary: duplicated line in history.md

Test Plan: n/a

Reviewers: yiwu

Reviewed By: yiwu

Subscribers: andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59433

Summary: update version and history

Test Plan: N/A

Reviewers: yiwu, sdong, IslamAbdelRahman, andrewkr

Reviewed By: andrewkr

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D59421

Summary: AFIK, options builder is not used by anyone. Remove it.

Test Plan: Run all existing tests.

Reviewers: IslamAbdelRahman, andrewkr, igor

Reviewed By: igor

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59319

Summary: Deprecate this one option and delete code and tests that are now superfluous.

Test Plan: all tests pass

Reviewers: igor, yhchiang, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: msalib, leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D55317

A couple "New Features" headers needed a blank line before them.

Summary:
Add a new option that can be used to set a specific compression algorithm for bottommost level.
This option will only affect levels larger than base level.

I have also updated CompactionJobInfo to include the compression algorithm used in compaction

Test Plan:
added new unittest
existing unittests

Reviewers: andrewkr, yhchiang, sdong

Reviewed By: sdong

Subscribers: lightmark, andrewkr, dhruba, yoshinorim

Differential Revision: https://reviews.facebook.net/D57669

Summary:
Add an option `iterator_readahead_size` to `ReadOptions` to enable
configurable readahead for iterators similar to the corresponding
option for compaction.

Test Plan:
```
make commit_prereq
```

Reviewers: kumar.rangarajan, ott, igor, sdong

Reviewed By: sdong

Subscribers: yiwu, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D55419

Summary: Release RocksDB 4.8.0

Test Plan: N/A

Reviewers: sdong, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D57525

Summary: Added EventListener::OnTableFileCreationStarted. EventListener::OnTableFileCreated will be called on failure case. User can check creation status via TableFileCreationInfo::status.

Test Plan: unit test.

Reviewers: dhruba, yhchiang, ott, sdong

Reviewed By: sdong

Subscribers: sdong, kradhakrishnan, IslamAbdelRahman, andrewkr, yhchiang, leveldb, ott, dhruba

Differential Revision: https://reviews.facebook.net/D56337

Summary:
This adds a new metablock containing a shared dictionary that is used
to compress all data blocks in the SST file. The size of the shared dictionary
is configurable in CompressionOptions and defaults to 0. It's currently only
used for zlib/lz4/lz4hc, but the block will be stored in the SST regardless of
the compression type if the user chooses a nonzero dictionary size.

During compaction, computes the dictionary by randomly sampling the first
output file in each subcompaction. It pre-computes the intervals to sample
by assuming the output file will have the maximum allowable length. In case
the file is smaller, some of the pre-computed sampling intervals can be beyond
end-of-file, in which case we skip over those samples and the dictionary will
be a bit smaller. After the dictionary is generated using the first file in a
subcompaction, it is loaded into the compression library before writing each
block in each subsequent file of that subcompaction.

On the read path, gets the dictionary from the metablock, if it exists. Then,
loads that dictionary into the compression library before reading each block.

Test Plan: new unit test

Reviewers: yhchiang, IslamAbdelRahman, cyan, sdong

Reviewed By: sdong

Subscribers: andrewkr, yoshinorim, kradhakrishnan, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D52287