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| author | unknown <dlenev@brandersnatch.localdomain> | 2004-03-28 04:11:54 +0400 |
|---|---|---|
| committer | unknown <dlenev@brandersnatch.localdomain> | 2004-03-28 04:11:54 +0400 |
| commit | f6a8ec5f925ec7d37d2858c5799b7a91a95accca (patch) | |
| tree | c5035ed539732100b50eb469c056b49a572c70d4 /BitKeeper | |
| parent | 2f74974b05a3f7469c0faebea9a157839dc0e4a6 (diff) | |
| download | mariadb-git-f6a8ec5f925ec7d37d2858c5799b7a91a95accca.tar.gz | |
"Fix" for BUG #2050 "10 to 1 performance drop with server 4.1.1".
Actually it is not a bug but right behavior observed as pefomance
degradation after we have forced Item_field::fix_fields() to
re-execute each time when we are executing prep stmt.
This patch implements small optimization which heals this bad
behavior. We are caching field position in TABLE::field array in
Item's member and are using this position for speeding up field
lookups in fix_fields() in case of its re-execution.
sql/item.cc:
Added cached_field_index member to Item_ident for caching field
position in TABLE::field array for quicker field lookup in case
fix_fields() is executed twice.
sql/item.h:
Added cached_field_index member to Item_ident for caching field
position in TABLE::field array for quicker field lookup in case
fix_fields() is executed twice.
sql/mysql_priv.h:
Now find_field_in_table has one more in-out parameter which is used
for caching field index in TABLE::field array stored for quicker
field look up.
sql/sql_acl.cc:
Now find_field_in_table has one more in-out parameter which is used
for caching field index in TABLE::field array stored for quicker
field look up.
sql/sql_base.cc:
Optimization: Now when we are looking up Field by its name we are
caching its position in TABLE::field array in Item_ident::cached_field_index,
so when we will call fix_fields() second time for this item (e.g.
when we are re-executing prep statement) we can reuse this index
to speed up this lookup.
sql/table.cc:
Now we storing in TABLE::name_hash pointers to elements of
TABLE::field array, because this allows easily retrieve index
of field in this array when it is looked up by its name.
sql/table.h:
Added comment claryfying what we store in TABLE::name_hash.
BitKeeper/etc/logging_ok:
Logging to logging@openlogging.org accepted
Diffstat (limited to 'BitKeeper')
| -rw-r--r-- | BitKeeper/etc/logging_ok | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/BitKeeper/etc/logging_ok b/BitKeeper/etc/logging_ok index 7a75d7a9873..1391f1e0a60 100644 --- a/BitKeeper/etc/logging_ok +++ b/BitKeeper/etc/logging_ok @@ -26,6 +26,7 @@ bk@admin.bk bk@mysql.r18.ru carsten@tsort.bitbybit.dk davida@isil.mysql.com +dlenev@brandersnatch.localdomain dlenev@build.mysql.com dlenev@mysql.com gerberb@ou800.zenez.com |