9f4c597d83
Summary: In places (e.g. GetSortedWals()) RocksDB relies on querying the file size or even reading the contents of files currently open for writing, and as in POSIX semantics, expects to see the flushed size and contents regardless of what has been synced. FaultInjectionTestFS historically did not emulate this behavior, only showing synced data from such read operations. (Different from FaultInjectionTestEnv--sigh.) This change makes the "proper" behavior the default behavior, at least for GetFileSize and FSSequentialFile. However, this new functionality is disabled in db_stress because of undiagnosed, unresolved issues. Also removes unused and confusing field `pos_at_last_flush_` This change is needed to support testing a relevant bug fix (in a follow-up diff). Other suggested follow-up: * Fix db_stress not to rely on the old behavior, and fix a related FIXME in db_stress_test_base.cc in LockWAL testing. * Fill in some corner cases in the FileSystem API for reading unsynced data (see new TODO items). * Consider deprecating and removing Flush() API functions from FileSystem APIs. It is not clear to me that there is a supported scenario in which they do anything but confuse API users and developers. If there is a use for them, it doesn't appear to be tested. Pull Request resolved: https://github.com/facebook/rocksdb/pull/12729 Test Plan: applies to all unit tests successfully, just updating the unit test from https://github.com/facebook/rocksdb/issues/12556 due to relying on the errant behavior. Also added a specific unit test Reviewed By: hx235 Differential Revision: D58091835 Pulled By: pdillinger fbshipit-source-id: f47a63b2b000f5875b6293a98577bff663d7fd33 |
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| buckifier | ||
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| 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 | ||
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| unreleased_history | ||
| util | ||
| utilities | ||
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| 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 | ||
| PLUGINS.md | ||
| README.md | ||
| TARGETS | ||
| USERS.md | ||
| Vagrantfile | ||
| WINDOWS_PORT.md | ||
| common.mk | ||
| crash_test.mk | ||
| issue_template.md | ||
| rocksdb.pc.in | ||
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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 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.