@ -56,13 +56,11 @@ const size_t kMaxCacheKeyPrefixSize __attribute__((unused)) =
// Read the block identified by "handle" from "file".
// The only relevant option is options.verify_checksums for now.
// Set *didIO to true if didIO is not null.
// On failure return non-OK.
// On success fill *result and return OK - caller owns *result
Status ReadBlockFromFile ( RandomAccessFile * file , const Footer & footer ,
const ReadOptions & options , const BlockHandle & handle ,
Block * * result , Env * env , bool * didIO = nullptr ,
bool do_uncompress = true ) {
Block * * result , Env * env , bool do_uncompress = true ) {
BlockContents contents ;
Status s = ReadBlockContents ( file , footer , options , handle , & contents , env ,
do_uncompress ) ;
@ -70,9 +68,6 @@ Status ReadBlockFromFile(RandomAccessFile* file, const Footer& footer,
* result = new Block ( contents ) ;
}
if ( didIO ! = nullptr ) {
* didIO = true ;
}
return s ;
}
@ -834,7 +829,7 @@ Iterator* BlockBasedTable::NewIndexIterator(const ReadOptions& read_options) {
// Convert an index iterator value (i.e., an encoded BlockHandle)
// into an iterator over the contents of the corresponding block.
Iterator * BlockBasedTable : : NewDataBlockIterator ( Rep * rep ,
const ReadOptions & ro , bool * didIO , const Slice & index_value ) {
const ReadOptions & ro , const Slice & index_value ) {
const bool no_io = ( ro . read_tier = = kBlockCacheTier ) ;
Cache * block_cache = rep - > options . block_cache . get ( ) ;
Cache * block_cache_compressed = rep - > options .
@ -872,7 +867,7 @@ Iterator* BlockBasedTable::NewDataBlockIterator(Rep* rep,
}
s = GetDataBlockFromCache ( key , ckey , block_cache , block_cache_compressed ,
statistics , ro , & block ) ;
statistics , ro , & block ) ;
if ( block . value = = nullptr & & ! no_io & & ro . fill_cache ) {
Histograms histogram = READ_BLOCK_GET_MICROS ;
@ -880,7 +875,7 @@ Iterator* BlockBasedTable::NewDataBlockIterator(Rep* rep,
{
StopWatch sw ( rep - > options . env , statistics , histogram ) ;
s = ReadBlockFromFile ( rep - > file . get ( ) , rep - > footer , ro , handle ,
& raw_block , rep - > options . env , didIO ,
& raw_block , rep - > options . env ,
block_cache_compressed = = nullptr ) ;
}
@ -898,7 +893,7 @@ Iterator* BlockBasedTable::NewDataBlockIterator(Rep* rep,
return NewErrorIterator ( Status : : Incomplete ( " no blocking io " ) ) ;
}
s = ReadBlockFromFile ( rep - > file . get ( ) , rep - > footer , ro , handle ,
& block . value , rep - > options . env , didIO ) ;
& block . value , rep - > options . env ) ;
}
Iterator * iter ;
@ -919,13 +914,13 @@ Iterator* BlockBasedTable::NewDataBlockIterator(Rep* rep,
class BlockBasedTable : : BlockEntryIteratorState : public TwoLevelIteratorState {
public :
BlockEntryIteratorState ( BlockBasedTable * table ,
const ReadOptions & read_options , bool * did_io )
: TwoLevelIteratorState ( table - > rep_ - > options . prefix_extractor ! = nullptr ) ,
table_ ( table ) , read_options_ ( read_options ) , did_io_ ( did_io ) { }
const ReadOptions & read_options )
: TwoLevelIteratorState ( table - > rep_ - > options . prefix_extractor ! = nullptr ) ,
table_ ( table ) ,
read_options_ ( read_options ) { }
Iterator * NewSecondaryIterator ( const Slice & index_value ) override {
return NewDataBlockIterator ( table_ - > rep_ , read_options_ , did_io_ ,
index_value ) ;
return NewDataBlockIterator ( table_ - > rep_ , read_options_ , index_value ) ;
}
bool PrefixMayMatch ( const Slice & internal_key ) override {
@ -936,8 +931,6 @@ class BlockBasedTable::BlockEntryIteratorState : public TwoLevelIteratorState {
// Don't own table_
BlockBasedTable * table_ ;
const ReadOptions read_options_ ;
// Don't own did_io_
bool * did_io_ ;
} ;
// This will be broken if the user specifies an unusual implementation
@ -1021,15 +1014,14 @@ bool BlockBasedTable::PrefixMayMatch(const Slice& internal_key) {
Iterator * BlockBasedTable : : NewIterator ( const ReadOptions & read_options ,
Arena * arena ) {
return NewTwoLevelIterator (
new BlockEntryIteratorState ( this , read_options , nullptr ) ,
NewIndexIterator ( read_options ) , arena ) ;
return NewTwoLevelIterator ( new BlockEntryIteratorState ( this , read_options ) ,
NewIndexIterator ( read_options ) , arena ) ;
}
Status BlockBasedTable : : Get (
const ReadOptions & read_options , const Slice & key , void * handle_context ,
bool ( * result_handler ) ( void * handle_context , const ParsedInternalKey & k ,
const Slice & v , bool didIO ) ,
const Slice & v ) ,
void ( * mark_key_may_exist_handler ) ( void * handle_context ) ) {
Status s ;
Iterator * iiter = NewIndexIterator ( read_options ) ;
@ -1052,9 +1044,8 @@ Status BlockBasedTable::Get(
RecordTick ( rep_ - > options . statistics . get ( ) , BLOOM_FILTER_USEFUL ) ;
break ;
} else {
bool didIO = false ;
unique_ptr < Iterator > block_iter (
NewDataBlockIterator ( rep_ , read_options , & didIO , iiter - > value ( ) ) ) ;
NewDataBlockIterator ( rep_ , read_options , iiter - > value ( ) ) ) ;
if ( read_options . read_tier & & block_iter - > status ( ) . IsIncomplete ( ) ) {
// couldn't get block from block_cache
@ -1071,8 +1062,8 @@ Status BlockBasedTable::Get(
s = Status : : Corruption ( Slice ( ) ) ;
}
if ( ! ( * result_handler ) ( handle_context , parsed_key , block_iter - > value ( ) ,
didIO ) ) {
if ( ! ( * result_handler ) ( handle_context , parsed_key ,
block_iter - > value ( ) ) ) {
done = true ;
break ;
}
@ -1089,22 +1080,34 @@ Status BlockBasedTable::Get(
return s ;
}
namespace {
bool SaveDidIO ( void * arg , const ParsedInternalKey & key , const Slice & value ,
bool didIO ) {
* reinterpret_cast < bool * > ( arg ) = didIO ;
return false ;
}
} // namespace
bool BlockBasedTable : : TEST_KeyInCache ( const ReadOptions & options ,
const Slice & key ) {
// We use Get() as it has logic that checks whether we read the
// block from the disk or not.
bool didIO = false ;
Status s = Get ( options , key , & didIO , SaveDidIO ) ;
std : : unique_ptr < Iterator > iiter ( NewIndexIterator ( options ) ) ;
iiter - > Seek ( key ) ;
assert ( iiter - > Valid ( ) ) ;
CachableEntry < Block > block ;
BlockHandle handle ;
Slice input = iiter - > value ( ) ;
Status s = handle . DecodeFrom ( & input ) ;
assert ( s . ok ( ) ) ;
return ! didIO ;
Cache * block_cache = rep_ - > options . block_cache . get ( ) ;
assert ( block_cache ! = nullptr ) ;
char cache_key_storage [ kMaxCacheKeyPrefixSize + kMaxVarint64Length ] ;
Slice cache_key =
GetCacheKey ( rep_ - > cache_key_prefix , rep_ - > cache_key_prefix_size , handle ,
cache_key_storage ) ;
Slice ckey ;
s = GetDataBlockFromCache ( cache_key , ckey , block_cache , nullptr , nullptr ,
options , & block ) ;
assert ( s . ok ( ) ) ;
bool in_cache = block . value ! = nullptr ;
if ( in_cache ) {
ReleaseCachedEntry ( block_cache , block . cache_handle ) ;
}
return in_cache ;
}
// REQUIRES: The following fields of rep_ should have already been populated:
Igor Canadi
10 years ago