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rocksdb: A persistent key-value store for flash storage
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Authors: * The Facebook Database Engineering Team
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* Build on earlier work on leveldb by Sanjay Ghemawat
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(sanjay@google.com) and Jeff Dean (jeff@google.com)
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This code is a library that forms the core building block for a fast
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key value server, especially suited for storing data on flash drives.
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It has an Log-Structured-Merge-Database (LSM) design with flexible tradeoffs
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between Write-Amplification-Factor(WAF), Read-Amplification-Factor (RAF)
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and Space-Amplification-Factor(SAF). It has multi-threaded compactions,
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making it specially suitable for storing multiple terabytes of data in a
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single database.
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The core of this code has been derived from open-source leveldb.
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The code under this directory implements a system for maintaining a
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persistent key/value store.
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See doc/index.html and github wiki (https://github.com/facebook/rocksdb/wiki)
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for more explanation.
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The public interface is in include/*. Callers should not include or
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rely on the details of any other header files in this package. Those
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internal APIs may be changed without warning.
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Guide to header files:
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include/rocksdb/db.h
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Main interface to the DB: Start here
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include/rocksdb/options.h
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Control over the behavior of an entire database, and also
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control over the behavior of individual reads and writes.
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include/rocksdb/comparator.h
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Abstraction for user-specified comparison function. If you want
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just bytewise comparison of keys, you can use the default comparator,
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but clients can write their own comparator implementations if they
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want custom ordering (e.g. to handle different character
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encodings, etc.)
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include/rocksdb/iterator.h
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Interface for iterating over data. You can get an iterator
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from a DB object.
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include/rocksdb/write_batch.h
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Interface for atomically applying multiple updates to a database.
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include/rocksdb/slice.h
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A simple module for maintaining a pointer and a length into some
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other byte array.
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include/rocksdb/status.h
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Status is returned from many of the public interfaces and is used
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to report success and various kinds of errors.
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include/rocksdb/env.h
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Abstraction of the OS environment. A posix implementation of
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this interface is in util/env_posix.cc
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include/rocksdb/table_builder.h
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Lower-level modules that most clients probably won't use directly
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include/rocksdb/cache.h
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An API for the block cache.
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include/rocksdb/compaction_filter.h
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An API for a application filter invoked on every compaction.
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include/rocksdb/filter_policy.h
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An API for configuring a bloom filter.
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include/rocksdb/memtablerep.h
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An API for implementing a memtable.
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include/rocksdb/statistics.h
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An API to retrieve various database statistics.
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include/rocksdb/transaction_log.h
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An API to retrieve transaction logs from a database.
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Design discussions are conducted in https://www.facebook.com/groups/rocksdb.dev/
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