09b6bf828a
Summary: Summary ======== `InlineSkipList<>::Insert` takes the `key` parameter as a C-string. Then, it performs multiple comparisons with it requiring the `GetLengthPrefixedSlice()` to be spawn in `MemTable::KeyComparator::operator()(const char* prefix_len_key1, const char* prefix_len_key2)` on the same data over and over. The patch tries to optimize that. Rough performance comparison ===== Big keys, no compression. ``` $ ./db_bench --writes 20000000 --benchmarks="fillrandom" --compression_type none -key_size 256 (...) fillrandom : 4.222 micros/op 236836 ops/sec; 80.4 MB/s ``` ``` $ ./db_bench --writes 20000000 --benchmarks="fillrandom" --compression_type none -key_size 256 (...) fillrandom : 4.064 micros/op 246059 ops/sec; 83.5 MB/s ``` TODO ====== In ~~a separated~~ this PR: - [x] Go outside the write path. Maybe even eradicate the C-string-taking variant of `KeyIsAfterNode` entirely. - [x] Try to cache the transformations applied by `KeyComparator` & friends in situations where we havy many comparisons with the same key. Closes https://github.com/facebook/rocksdb/pull/3516 Differential Revision: D7059300 Pulled By: ajkr fbshipit-source-id: 6f027dbb619a488129f79f79b5f7dbe566fb2dbb |
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buckifier | ||
build_tools | ||
cache | ||
cmake | ||
coverage | ||
db | ||
docs | ||
env | ||
examples | ||
hdfs | ||
include/rocksdb | ||
java | ||
memtable | ||
monitoring | ||
options | ||
port | ||
table | ||
third-party | ||
tools | ||
util | ||
utilities | ||
.clang-format | ||
.gitignore | ||
.travis.yml | ||
appveyor.yml | ||
AUTHORS | ||
CMakeLists.txt | ||
CODE_OF_CONDUCT.md | ||
CONTRIBUTING.md | ||
COPYING | ||
DEFAULT_OPTIONS_HISTORY.md | ||
DUMP_FORMAT.md | ||
HISTORY.md | ||
INSTALL.md | ||
issue_template.md | ||
LANGUAGE-BINDINGS.md | ||
LICENSE.Apache | ||
LICENSE.leveldb | ||
Makefile | ||
README.md | ||
ROCKSDB_LITE.md | ||
src.mk | ||
TARGETS | ||
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/
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.