@ -26,13 +26,13 @@ namespace rocksdb {
// See e.g. RocksDB DynamicBloom.
// See e.g. RocksDB DynamicBloom.
//
//
class LegacyNoLocalityBloomImpl { class LegacyNoLocalityBloomImpl {
public : public :
static inline void AddHash ( uint32_t h , uint32_t total_bits , static inline void AddHash ( uint32_t h , uint32_t total_bits , int num_probes ,
int num_probes , char * data ) { char * data ) {
const uint32_t delta = ( h > > 17 ) | ( h < < 15 ) ; // Rotate right 17 bits
const uint32_t delta = ( h > > 17 ) | ( h < < 15 ) ; // Rotate right 17 bits
for ( int i = 0 ; i < num_probes ; i + + ) { for ( int i = 0 ; i < num_probes ; i + + ) {
const uint32_t bitpos = h % total_bits ; const uint32_t bitpos = h % total_bits ;
data [ bitpos / 8 ] | = ( 1 < < ( bitpos % 8 ) ) ; data [ bitpos / 8 ] | = ( 1 < < ( bitpos % 8 ) ) ;
h + = delta ; h + = delta ;
} }
} }
@ -42,7 +42,7 @@ public:
const uint32_t delta = ( h > > 17 ) | ( h < < 15 ) ; // Rotate right 17 bits
const uint32_t delta = ( h > > 17 ) | ( h < < 15 ) ; // Rotate right 17 bits
for ( int i = 0 ; i < num_probes ; i + + ) { for ( int i = 0 ; i < num_probes ; i + + ) {
const uint32_t bitpos = h % total_bits ; const uint32_t bitpos = h % total_bits ;
if ( ( data [ bitpos / 8 ] & ( 1 < < ( bitpos % 8 ) ) ) = = 0 ) { if ( ( data [ bitpos / 8 ] & ( 1 < < ( bitpos % 8 ) ) ) = = 0 ) {
return false ; return false ;
} }
h + = delta ; h + = delta ;
@ -51,7 +51,6 @@ public:
} }
} ; } ;
// A legacy Bloom filter implementation with probes local to a single
// A legacy Bloom filter implementation with probes local to a single
// cache line (fast). Because SST files might be transported between
// cache line (fast). Because SST files might be transported between
// platforms, the cache line size is a parameter rather than hard coded.
// platforms, the cache line size is a parameter rather than hard coded.
@ -72,15 +71,15 @@ public:
//
//
template < bool ExtraRotates > template < bool ExtraRotates >
class LegacyLocalityBloomImpl { class LegacyLocalityBloomImpl {
private : private :
static inline uint32_t GetLine ( uint32_t h , uint32_t num_lines ) { static inline uint32_t GetLine ( uint32_t h , uint32_t num_lines ) {
uint32_t offset_h = ExtraRotates ? ( h > > 11 ) | ( h < < 21 ) : h ; uint32_t offset_h = ExtraRotates ? ( h > > 11 ) | ( h < < 21 ) : h ;
return offset_h % num_lines ; return offset_h % num_lines ;
} }
public :
static inline void AddHash ( uint32_t h , uint32_t num_lines , public :
int num_probes , char * data , static inline void AddHash ( uint32_t h , uint32_t num_lines , int num_probes ,
int log2_cache_line_bytes ) { char * data , int log2_cache_line_bytes ) {
const int log2_cache_line_bits = log2_cache_line_bytes + 3 ; const int log2_cache_line_bits = log2_cache_line_bytes + 3 ;
char * data_at_offset = char * data_at_offset =
@ -99,12 +98,12 @@ public:
static inline void PrepareHashMayMatch ( uint32_t h , uint32_t num_lines , static inline void PrepareHashMayMatch ( uint32_t h , uint32_t num_lines ,
const char * data , const char * data ,
uint32_t /*out*/ * byte_offset , uint32_t /*out*/ * byte_offset ,
int log2_cache_line_bytes ) { int log2_cache_line_bytes ) {
uint32_t b = GetLine ( h , num_lines ) < < log2_cache_line_bytes ; uint32_t b = GetLine ( h , num_lines ) < < log2_cache_line_bytes ;
PREFETCH ( data + b , 0 /* rw */ , 1 /* locality */ ) ; PREFETCH ( data + b , 0 /* rw */ , 1 /* locality */ ) ;
PREFETCH ( data + b + ( ( 1 < < log2_cache_line_bytes ) - 1 ) , PREFETCH ( data + b + ( ( 1 < < log2_cache_line_bytes ) - 1 ) , 0 /* rw */ ,
0 /* rw */ , 1 /* locality */ ) ; 1 /* locality */ ) ;
* byte_offset = b ; * byte_offset = b ;
} }
@ -112,8 +111,7 @@ public:
int num_probes , const char * data , int num_probes , const char * data ,
int log2_cache_line_bytes ) { int log2_cache_line_bytes ) {
uint32_t b = GetLine ( h , num_lines ) < < log2_cache_line_bytes ; uint32_t b = GetLine ( h , num_lines ) < < log2_cache_line_bytes ;
return HashMayMatchPrepared ( h , num_probes , return HashMayMatchPrepared ( h , num_probes , data + b , log2_cache_line_bytes ) ;
data + b , log2_cache_line_bytes ) ;
} }
static inline bool HashMayMatchPrepared ( uint32_t h , int num_probes , static inline bool HashMayMatchPrepared ( uint32_t h , int num_probes ,
sdong
5 years ago
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