mirror/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2026-05-15 19:37:16 +02:00
Code Issues Projects Releases Packages Wiki Activity

A minor change to MySQL's hash where calculation of hash can be done separately to avoid doing it under contended mutex locks

Browse source
This commit is contained in:
Mikael Ronstrom 2009-10-09 14:22:22 +02:00
commit d3540b216f
3 changed files with 43 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

29
mysys/hash.c
View file

@ -214,6 +214,20 @@ uchar* my_hash_search(const HASH *hash, const uchar *key, size_t length)
return my_hash_first(hash, key, length, &state);
}
uchar* my_hash_search_using_hash_value(const HASH *hash,
uint hash_value,
const uchar *key,
size_t length)
{
HASH_SEARCH_STATE state;
return my_hash_first_from_hash_value(hash, hash_value,
key, length, &state);
}
uint my_calc_hash(const HASH *hash, const uchar *key, size_t length)
{
return calc_hash(hash, key, length ? length : hash->key_length);
}
/*
Search after a record based on a key
@ -223,15 +237,26 @@ uchar* my_hash_search(const HASH *hash, const uchar *key, size_t length)
uchar* my_hash_first(const HASH *hash, const uchar *key, size_t length,
HASH_SEARCH_STATE *current_record)
{
return my_hash_first_from_hash_value(hash,
calc_hash(hash, key, length ? length : hash->key_length),
key, length, current_record);
}
uchar* my_hash_first_from_hash_value(const HASH *hash,
uint hash_value,
const uchar *key,
size_t length,
HASH_SEARCH_STATE *current_record)
{
HASH_LINK *pos;
uint flag,idx;
DBUG_ENTER("my_hash_first");
DBUG_ENTER("my_hash_first_from_hash_value");
flag=1;
if (hash->records)
{
idx= my_hash_mask(calc_hash(hash, key, length ? length : hash->key_length),
idx= my_hash_mask(hash_value,
hash->blength, hash->records);
do
{