54d94e9c2c
Summary: Currently the point lookup values are copied to a string provided by the user. This incures an extra memcpy cost. This patch allows doing point lookup via a PinnableSlice which pins the source memory location (instead of copying their content) and releases them after the content is consumed by the user. The old API of Get(string) is translated to the new API underneath. Here is the summary for improvements: 1. value 100 byte: 1.8% regular, 1.2% merge values 2. value 1k byte: 11.5% regular, 7.5% merge values 3. value 10k byte: 26% regular, 29.9% merge values The improvement for merge could be more if we extend this approach to pin the merge output and delay the full merge operation until the user actually needs it. We have put that for future work. PS: Sometimes we observe a small decrease in performance when switching from t5452014 to this patch but with the old Get(string) API. The difference is a little and could be noise. More importantly it is safely cancelled Closes https://github.com/facebook/rocksdb/pull/1732 Differential Revision: D4374613 Pulled By: maysamyabandeh fbshipit-source-id: a077f1a |
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| arcanist_util | ||
| build_tools | ||
| cmake/modules | ||
| coverage | ||
| db | ||
| docs | ||
| examples | ||
| hdfs | ||
| include/rocksdb | ||
| java | ||
| memtable | ||
| port | ||
| table | ||
| third-party | ||
| tools | ||
| util | ||
| utilities | ||
| .arcconfig | ||
| .clang-format | ||
| .gitignore | ||
| .travis.yml | ||
| appveyor.yml | ||
| AUTHORS | ||
| CMakeLists.txt | ||
| CONTRIBUTING.md | ||
| DEFAULT_OPTIONS_HISTORY.md | ||
| DUMP_FORMAT.md | ||
| HISTORY.md | ||
| INSTALL.md | ||
| LANGUAGE-BINDINGS.md | ||
| LICENSE | ||
| Makefile | ||
| PATENTS | ||
| README.md | ||
| ROCKSDB_LITE.md | ||
| src.mk | ||
| thirdparty.inc | ||
| USERS.md | ||
| Vagrantfile | ||
| WINDOWS_PORT.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/