Re: syslog performance when logging big statements

=CE=A3=CF=84=CE=B9=CF=82 Tuesday 08 July 2008 17:35:16 =CE=BF/=CE=B7 Tom
La=
ne =CE=AD=CE=B3=CF=81=CE=B1=CF=88=CE=B5:
> Achilleas Mantzios <achill@[EMAIL PROTECTED]
> writes:
> > In this case, the INSERT *needs* 20 minutes to return. This is because
=
the logging through syslog seems to severely slow the system.
> > If instead, i use stderr, even with logging_collector=3Don, the same
st=
atement needs 15 seconds to return.
>=20
> Hmm.  There's a function in elog.c that breaks log messages into chunks
> for syslog.  I don't think anyone's ever looked hard at its performance
> --- maybe there's an O(N^2) behavior?
>=20
> 			regards, tom lane
>=20

Thanx,
i changed PG_SYSLOG_LIMIT in elog.c:1269 from 128 to 1048576
#ifndef PG_SYSLOG_LIMIT
/* #define PG_SYSLOG_LIMIT 128 */
#define PG_SYSLOG_LIMIT 1048576
#endif

and i got super fast stderr performance. :)

However, i noticed a certain amount of data in the log is lost.
Didnt dig much to the details tho.

--=20
Achilleas Mantzios

--=20
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