rocksdb README file.

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rocksdb README file.

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README

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+rocksdb: A persistent key-value store for flash storage
+Authors: The Facebook Database Engineering Team
+
+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 an Log-Stuctured-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.
+
+The core of this code has been derived from open-source leveldb.
+
 leveldb: A key-value store
 Authors: Sanjay Ghemawat (sanjay@google.com) and Jeff Dean (jeff@google.com)