On Sat, Nov 2, 2013 at 11:54 AM, Евгений Селявка <evg.selyavka@gmail.com> wrote:
> DB size is about 20GB. There is no high write activity on DB. But
> periodically in postgresql log i see for example: "select 1" duration is
> about 500-1000 ms.
>
> In this period of time response time from db terribly. This period of time
> not bound with high traffic. It is not other app on the server. There is not
> specific cron job on server.
Have you shown all the modified kernel settings? Don't you use huge
pages accidentally? It might be a transparent huge pages
defragmentation issue, the symptoms look similar.
Another thing that might cause it is network. Try to monitor it at the
time of these stalls.
--
Kind regards,
Sergey Konoplev
PostgreSQL Consultant and DBA
http://www.linkedin.com/in/grayhemp
+1 (415) 867-9984, +7 (901) 903-0499, +7 (988) 888-1979
gray.ru@gmail.com
