3bde41b5a3
Summary: Currently, when the block cache is used for the filter block, it is not really the block itself that is stored in the cache but a FilterBlockReader object. Since this object is not pure data (it has, for instance, pointers that might dangle, including in one case a back pointer to the TableReader), it's not really sharable. To avoid the issues around this, the current code erases the cache entries when the TableReader is closed (which, BTW, is not sufficient since a concurrent TableReader might have picked up the object in the meantime). Instead of doing this, the patch moves the FilterBlockReader out of the cache altogether, and decouples the filter reader object from the filter block. In particular, instead of the TableReader owning, or caching/pinning the FilterBlockReader (based on the customer's settings), with the change the TableReader unconditionally owns the FilterBlockReader, which in turn owns/caches/pins the filter block. This change also enables us to reuse the code paths historically used for data blocks for filters as well. Note: Eviction statistics for filter blocks are temporarily broken. We plan to fix this in a separate phase. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5504 Test Plan: make asan_check Differential Revision: D16036974 Pulled By: ltamasi fbshipit-source-id: 770f543c5fb4ed126fd1e04bfd3809cf4ff9c091 |
||
|---|---|---|
| buckifier | ||
| build_tools | ||
| cache | ||
| cmake | ||
| coverage | ||
| db | ||
| docs | ||
| env | ||
| examples | ||
| file | ||
| hdfs | ||
| include/rocksdb | ||
| java | ||
| logging | ||
| memory | ||
| memtable | ||
| monitoring | ||
| options | ||
| port | ||
| table | ||
| test_util | ||
| third-party/gtest-1.7.0/fused-src/gtest | ||
| tools | ||
| trace_replay | ||
| util | ||
| utilities | ||
| .clang-format | ||
| .gitignore | ||
| .lgtm.yml | ||
| .travis.yml | ||
| AUTHORS | ||
| CMakeLists.txt | ||
| CODE_OF_CONDUCT.md | ||
| CONTRIBUTING.md | ||
| COPYING | ||
| DEFAULT_OPTIONS_HISTORY.md | ||
| DUMP_FORMAT.md | ||
| HISTORY.md | ||
| INSTALL.md | ||
| LANGUAGE-BINDINGS.md | ||
| LICENSE.Apache | ||
| LICENSE.leveldb | ||
| Makefile | ||
| README.md | ||
| ROCKSDB_LITE.md | ||
| TARGETS | ||
| USERS.md | ||
| Vagrantfile | ||
| WINDOWS_PORT.md | ||
| appveyor.yml | ||
| defs.bzl | ||
| issue_template.md | ||
| src.mk | ||
| thirdparty.inc | ||
README.md
RocksDB: A Persistent Key-Value Store for Flash and RAM Storage
RocksDB is developed and maintained by Facebook Database Engineering Team. It is built on earlier work on LevelDB by Sanjay Ghemawat (sanjay@google.com) and Jeff Dean (jeff@google.com)
This code is a library that forms the core building block for a fast key value server, especially suited for storing data on flash drives. It has a Log-Structured-Merge-Database (LSM) design with flexible tradeoffs between Write-Amplification-Factor (WAF), Read-Amplification-Factor (RAF) and Space-Amplification-Factor (SAF). It has multi-threaded compactions, making it specially suitable for storing multiple terabytes of data in a single database.
Start with example usage here: https://github.com/facebook/rocksdb/tree/master/examples
See the github wiki for more explanation.
The public interface is in include/. Callers should not include or
rely on the details of any other header files in this package. Those
internal APIs may be changed without warning.
Design discussions are conducted in https://www.facebook.com/groups/rocksdb.dev/
License
RocksDB is dual-licensed under both the GPLv2 (found in the COPYING file in the root directory) and Apache 2.0 License (found in the LICENSE.Apache file in the root directory). You may select, at your option, one of the above-listed licenses.