3d67b5e8e5
Summary: Implement block cache lookup to determine readahead_size during scans. It's enabled if auto_readahead_size, block_cache and iterate_upper_bound - all three are set. Design - 1. Whenever there is a cache miss and FilePrefetchBuffer is called, a callback is made to determine readahead_size for that prefetching. 2. The callback iterates over index and do block cache lookup for each data block handle until existing readahead_size is reached. Then It removes the cache hit data blocks from end to calculate optimized readahead_size. 3. Since index_iter_ is moved, it stores block handles in a queue, and use that queue to get block handle instead of doing index_iter_->Next(). 4. This is for Sync scans. Async scans support is in progress. NOTE: The issue right now is after Seek and Next, if Prev is called, there is no way to do Prev operation. index_iter_ is already pointing to a different block. So it returns "Not supported" in that case with error message - "auto tuning of readahead size is not supported with Prev op" Pull Request resolved: https://github.com/facebook/rocksdb/pull/11860 Test Plan: - Added new unit test - crash_tests - Running scans locally to check for any regression Reviewed By: anand1976 Differential Revision: D49548118 Pulled By: akankshamahajan15 fbshipit-source-id: f1aee409a71b4ad9e5bf3610f43edf30c6630c78 |
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.circleci | ||
.github/workflows | ||
buckifier | ||
build_tools | ||
cache | ||
cmake | ||
coverage | ||
db | ||
db_stress_tool | ||
docs | ||
env | ||
examples | ||
file | ||
fuzz | ||
include/rocksdb | ||
java | ||
logging | ||
memory | ||
memtable | ||
microbench | ||
monitoring | ||
options | ||
plugin | ||
port | ||
table | ||
test_util | ||
third-party | ||
tools | ||
trace_replay | ||
unreleased_history | ||
util | ||
utilities | ||
.clang-format | ||
.gitignore | ||
.lgtm.yml | ||
.watchmanconfig | ||
AUTHORS | ||
CMakeLists.txt | ||
CODE_OF_CONDUCT.md | ||
common.mk | ||
CONTRIBUTING.md | ||
COPYING | ||
crash_test.mk | ||
DEFAULT_OPTIONS_HISTORY.md | ||
DUMP_FORMAT.md | ||
HISTORY.md | ||
INSTALL.md | ||
issue_template.md | ||
LANGUAGE-BINDINGS.md | ||
LICENSE.Apache | ||
LICENSE.leveldb | ||
Makefile | ||
PLUGINS.md | ||
README.md | ||
rocksdb.pc.in | ||
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 especially suitable for storing multiple terabytes of data in a single database.
Start with example usage here: https://github.com/facebook/rocksdb/tree/main/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.
Questions and discussions are welcome on the RocksDB Developers Public Facebook group and email list on Google Groups.
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.