diff options
Diffstat (limited to 'storage/heap/hp_create.c')
| -rw-r--r-- | storage/heap/hp_create.c | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/storage/heap/hp_create.c b/storage/heap/hp_create.c index 22ab9b54a85..d170d1abc65 100644 --- a/storage/heap/hp_create.c +++ b/storage/heap/hp_create.c @@ -245,21 +245,32 @@ static void init_block(HP_BLOCK *block, uint reclength, ulong min_records, { uint i,recbuffer,records_in_block; - max_records= max(min_records,max_records); + /* + If not min_records and max_records are given, optimize for 1000 rows + */ + if (!min_records) + min_records= min(1000, max_records); if (!max_records) - max_records= 1000; /* As good as quess as anything */ - recbuffer= (uint) (reclength + sizeof(uchar**) - 1) & ~(sizeof(uchar**) - 1); - records_in_block= max_records / 10; + max_records= max(min_records, 1000); /* We don't want too few records_in_block as otherwise the overhead of of the HP_PTRS block will be too notable */ - records_in_block= min(1000, max_records); + records_in_block= max(1000, min_records); + records_in_block= min(records_in_block, max_records); + /* If big max_records is given, allocate bigger blocks */ + records_in_block= max(records_in_block, max_records / 10); + /* We don't want too few blocks per row either */ if (records_in_block < 10) records_in_block= 10; - /* The + 1 is there to ensure that we get at least 1 row per level */ + recbuffer= (uint) (reclength + sizeof(uchar**) - 1) & ~(sizeof(uchar**) - 1); + /* + Don't allocate more than my_default_record_cache_size per level. + The + 1 is there to ensure that we get at least 1 row per level (for + the exceptional case of very long rows) + */ if (records_in_block*recbuffer > (my_default_record_cache_size-sizeof(HP_PTRS)*HP_MAX_LEVELS)) records_in_block= (my_default_record_cache_size - sizeof(HP_PTRS) * |