Re: [PERFORM] How to diagnose a “context-switching ” storm problem ?

2010/4/12 RD黄永卫 <yongwei_huang(at)temp(dot)gtmc(dot)com(dot)cn>:
> I donnt know what make the "context-switching" storm ？
>
> How should I investigate the real reason ?
>
> Could you please give me some advice ?

It might be because of cascading locks so try to monitor them when it happens.

You may find this query useful:

SELECT
granted,
count(1) AS locks,
pid,
now() - xact_start AS xact_age,
now() - query_start AS query_age,
current_query
FROM
pg_locks AS l
LEFT JOIN pg_stat_activity AS a ON
pid = procpid
GROUP BY 1, 3, 4, 5, 6
ORDER BY 1 DESC, 2 DESC
-- ORDER BY 4 DESC
LIMIT 100;

--
Sergey Konoplev

Blog: http://gray-hemp.blogspot.com /
Linkedin: http://ru.linkedin.com/in/grayhemp /
JID/GTalk: gray(dot)ru(at)gmail(dot)com / Skype: gray-hemp / ICQ: 29353802