rocksdb/HISTORY.md
kailiu 84f8185fc0 Merge branch 'master' into performance
Conflicts:
	HISTORY.md
	db/db_impl.cc
	db/memtable.cc
2014-02-05 21:21:00 -08:00

2.6 KiB

Rocksdb Change Log

Unreleased

Public API changes

  • Removed arena.h from public header files.
  • By default, checksums are verified on every read from database

master

2.7.0 (01/28/2014)

Public API changes

  • Renamed StackableDB::GetRawDB() to StackableDB::GetBaseDB().
  • Renamed WriteBatch::Data() const std::string& Data() const.
  • Renamed class TableStats to TableProperties.
  • Deleted class PrefixHashRepFactory. Please use NewHashSkipListRepFactory() instead.
  • Supported multi-threaded EnableFileDeletions() and DisableFileDeletions().
  • Added DB::GetOptions().
  • Added DB::GetDbIdentity().

New Features

  • Added BackupableDB
  • Implemented TailingIterator, a special type of iterator that doesn't create a snapshot (can be used to read newly inserted data) and is optimized for doing sequential reads.
  • Added property block for table, which allows (1) a table to store its metadata and (2) end user to collect and store properties they are interested in.
  • Enabled caching index and filter block in block cache (turned off by default).
  • Supported error report when doing manual compaction.
  • Supported additional Linux platform flavors and Mac OS.
  • Put with SliceParts - Variant of Put() that gathers output like writev(2)
  • Bug fixes and code refactor for compatibility with upcoming Column Family feature.

Performance Improvements

  • Huge benchmark performance improvements by multiple efforts. For example, increase in readonly QPS from about 530k in 2.6 release to 1.1 million in 2.7 [1]
  • Speeding up a way RocksDB deleted obsolete files - no longer listing the whole directory under a lock -- decrease in p99
  • Use raw pointer instead of shared pointer for statistics: 5b825d -- huge increase in performance -- shared pointers are slow
  • Optimized locking for Get() -- 1fdb3f -- 1.5x QPS increase for some workloads
  • Cache speedup - e8d40c3
  • Implemented autovector, which allocates first N elements on stack. Most of vectors in RocksDB are small. Also, we never want to allocate heap objects while holding a mutex. -- c01676e4
  • Lots of efforts to move malloc, memcpy and IO outside of locks