query cache to disable totally

[Vadim Tkachenko]

even if query cache is not used (size=0), sometimes I see stalls like

      4 pthread_cond_wait@@GLIBC_2.3.2
Query_cache::lock(sql_cache.cc:717)
Query_cache::invalidate_table(sql_cache.cc:2933)
Query_cache::invalidate_table(sql_cache.cc:2904)
Query_cache::invalidate(sql_cache.cc:1971)
mysql_update(sql_update.cc:791)
mysql_execute_command(sql_parse.cc:3160)
mysql_parse(sql_parse.cc:6125)
dispatch_command(sql_parse.cc:1257)
do_command(sql_parse.cc:895)
handle_one_connection(sql_connect.cc:1736)
start_thread
clone

We need to avoid any query_cache call if it is not used ( size=0)

[Swany (greenlion)]

In MySQL 5.5 it is my understand that the query cache mutex is never
held if the server starts with query_cache_type=0. Maybe we should
backport that to Percona Server?

On Fri, Jul 23, 2010 at 12:28 AM, Oleg Tsarev <email address hidden> wrote:
> ** Changed in: percona-server
>       Status: Triaged => In Progress
>
> --
> query cache to disable totally
> https://bugs.launchpad.net/bugs/609027
> You received this bug notification because you are a member of Percona
> developers, which is the registrant for Percona Server.
>

[Kenny Gryp (gryp)]

For reference purposes: corresponding mysql bug: http://bugs.mysql.com/bug.php?id=38551

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PS-1151