Thread: postgres getting slow
I noticed that on our postgres server, when more than say 15-20 backends are open at once, things start to get real slow. System is: Redhat 5.2 Linux 2.2.8 kernel Postgres 6.3.2 PII 450 256MB RAM Does anyone know why this may be? Also I can't seem to get postgres to write to a log about what it is doing, whats the best way to get it to do this, so that any errors/warnings get logged? Brian ----------------------------------------------------- Brian Feeny (BF304) signal@shreve.net 318-222-2638 x 109 http://www.shreve.net/~signal Network Administrator ShreveNet Inc. (ASN 11881)
> I noticed that on our postgres server, when more than say 15-20 backends > are open at once, things start to get real slow. System is: > > Redhat 5.2 Linux > 2.2.8 kernel > Postgres 6.3.2 > PII 450 > 256MB RAM > > Does anyone know why this may be? Hmmm... I'm trying to optimize Postgres as much as I can right now. I usually have 4 or 5 backends running, some under CGI and some under ODBC. I notice the ODBC (via Access) seems to monopolize the database, especially when doing updates. > Also I can't seem to get postgres to write to a log about what it is > doing, whats the best way to get it to do this, so that any > errors/warnings get logged? I have something like this in my startup script appended to the invocation of the postmaster ( as we discussed yesterday): >> ${PGLOGFILE} 2>&1 where $PGLOGFILE is a path to postgres.log. Brett W. McCoy http://www.lan2wan.com/~bmccoy/ ----------------------------------------------------------------------- "One basic notion underlying Usenet is that it is a cooperative." Having been on USENET for going on ten years, I disagree with this. The basic notion underlying USENET is the flame. -- Chuq Von Rospach
> > I have something like this in my startup script appended to the invocation > of the postmaster ( as we discussed yesterday): > > >> ${PGLOGFILE} 2>&1 > > where $PGLOGFILE is a path to postgres.log. > What sort of things to do you catch with logging this? I haven't seen a single thing goto this file since starting it: export PGLOGFILE=/var/lib/pgsql/pg.log su postgres -c '/usr/bin/postmaster -B 250 -i -S -D/var/lib/pgsql -o -S 1024 >> ${PGLOGFILE} 2>&1' [signal@norad signal]$ ls -al /var/lib/pgsql/pg.log -rw-rw-r-- 1 postgres postgres 0 May 14 11:31 /var/lib/pgsql/pg.log > Brett W. McCoy > http://www.lan2wan.com/~bmccoy/ > ----------------------------------------------------------------------- > "One basic notion underlying Usenet is that it is a cooperative." > > Having been on USENET for going on ten years, I disagree with this. > The basic notion underlying USENET is the flame. > -- Chuq Von Rospach > ----------------------------------------------------- Brian Feeny (BF304) signal@shreve.net 318-222-2638 x 109 http://www.shreve.net/~signal Network Administrator ShreveNet Inc. (ASN 11881)
At 21:51 +0300 on 20/05/1999, Brian wrote: > What sort of things to do you catch with logging this? I haven't seen a > single thing goto this file since starting it: > > export PGLOGFILE=/var/lib/pgsql/pg.log > su postgres -c '/usr/bin/postmaster -B 250 -i -S -D/var/lib/pgsql -o -S >1024 >> ${PGLOGFILE} 2>&1' I usually add "-d 2" to my postmaster invocation. It puts a lot of information in the logfile, although I must say I've never been happy about Postgres's logs. If you want to see where an error has occured, the actual query is buried within many internal messages. Herouth -- Herouth Maoz, Internet developer. Open University of Israel - Telem project http://telem.openu.ac.il/~herutma