Re: Number of open files - Mailing list pgsql-general

From Tom Lane
Subject Re: Number of open files
Date
Msg-id 28409.981561385@sss.pgh.pa.us
Whole thread Raw
In response to Re: Number of open files  ("Mark Alliban" <MarkA@idnltd.com>)
Responses Backends hanging around (was Re: Number of open files)  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
"Mark Alliban" <MarkA@idnltd.com> writes:
> I have increased file-max to 16000. However after about 24 hours of running,
> pgsql crashed and errors in the log showed that the system had run out of
> memory. I do not have the exact error message, as I was in a hurry to get
> the system up and running again (it is a live production system). The system
> has 512MB memory and there were 47 ODBC sessions in progress, so I cannot
> believe that the system *really* ran out of memory.

Oh, I could believe that, depending on what your ODBC clients were
doing.  10 meg of working store per backend is not out of line for
complex queries.  Have you tried watching with 'top' to see what a
typical backend process size actually is for your workload?

Also, the amount of RAM isn't necessarily the limiting factor here;
what you should have told us is how much swap space you have ...

> Also backends seem to hang around for about a minute after I close the ODBC
> connections. Is this normal?

Seems odd to me too.

            regards, tom lane

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