Re: PG Logging is Slow

On Mon, Dec 20, 2004 at 03:17:11PM +1100, Theo Galanakis wrote:
> Under postgres 7.3 logging is incredibly slow!
>
> I have applied the following settings:
>
> syslog = 2
> syslog_facility = 'LOCAL0'
> syslog_ident = 'postgres'
>
> log_connections = true
> log_duration = true
> log_pid = true
> log_statement = true
> log_timestamp = true
>
> This severely impacted the performance of our production system, a search
> page which took 1-3 seconds now takes over 30, is this normal?
>
> I need to get some performance indicators from our production db, however I
> cant turn on logging with such performance degradation.

I've experienced this problem many times due to hanging dns
lookups. /etc/resolv.conf may point to a nonexistent
nameserver. Comment it out and restart syslogd. Or use a syslog
implementation that allows you to disable dns lookups. Or just give
the nameserver a kick.

-Mike Adler