[rt-users] RT hangs with 'SELECT GET_LOCK' slow query log entries

[Jesse Vincent]

On Dec 5, 2006, at 7:26 AM, Steve Ison wrote:

> Hello,
>
> My RT installation (3.6.1, MySQL 5, Apache 1.3, mod_perl 1.9,  
> DBIx::SearchBuilder v1.45) has slowed considerably as the number of  
> tickets has grown. In the MySQL slow query log I see:
>
> # Time: 061205 11:52:19
> # User at Host: rt_user[rt_user] @ localhost []
> # Query_time: 181  Lock_time: 0  Rows_sent: 1  Rows_examined: 0
> SELECT GET_LOCK('Apache-Session-b59f829ebcd37237783322425399eeb2',  
> 3600);
>
> While this is happening apache just spins using all the cpu.
>
> While trawling back the the mailing-list archives I noticed others  
> have had this problem, but I can't find any mention of a solution.  
> Am I missing it or is this an ongoing problem?
>

This happens when RT is still serving a page to the user with that  
session and the user requests another page.   Sometimes, switching to  
another Apache::Session backend can help.


> Thanks,
> Steve.
> -- 
> Stephen Ison
> Unix Support
> University of Cambridge Computing Service
> si202 at cam.ac.uk
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