rocksdb/util/murmurhash.h
Dhruba Borthakur f7975ac733 Implement RowLocks for assoc schema
Summary:
Each assoc is identified by (id1, assocType). This is the rowkey.
Each row has a read/write rowlock. There is statically allocated array
of 2000 read/write locks. A rowkey is murmur-hashed to one of the
read/write locks.

assocPut and assocDelete acquires the rowlock in Write mode.
The key-updates are done within the rowlock with a atomic nosync
batch write to leveldb. Then the rowlock is released and
a write-with-sync is done to sync leveldb transaction log.

Test Plan: added unit test

Reviewers: heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D5859
2012-10-03 23:19:01 -07:00

33 lines
854 B
C

/*
Murmurhash from http://sites.google.com/site/murmurhash/
All code is released to the public domain. For business purposes, Murmurhash is
under the MIT license.
*/
#ifndef MURMURHASH_H
#define MURMURHASH_H
#include <stdint.h>
#if defined(__x86_64__)
#define MURMUR_HASH MurmurHash64A
uint64_t MurmurHash64A ( const void * key, int len, unsigned int seed );
#define MurmurHash MurmurHash64A
typedef uint64_t murmur_t;
#elif defined(__i386__)
#define MURMUR_HASH MurmurHash2
unsigned int MurmurHash2 ( const void * key, int len, unsigned int seed );
#define MurmurHash MurmurHash2
typedef unsigned int murmur_t;
#else
#define MURMUR_HASH MurmurHashNeutral2
unsigned int MurmurHashNeutral2 ( const void * key, int len, unsigned int seed );
#define MurmurHash MurmurHashNeutral2
typedef unsigned int murmur_t;
#endif
#endif /* MURMURHASH_H */