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

2010/4/12 RD黄永卫 <yongwei_huang@temp.gtmc.com.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;


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Sergey Konoplev

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