Helle there,

My name is Bernhard Grün, I am from Germany and I am one of the
administrators of http://www.gesichterparty.de/ . This
is a quite
large party community site that runs pound to balance the web traffic
across backend servers (3 backends at the moment). In average we have
about 700 requests per second. Pound is already on its own dedicated
server (Pentium D 805, 1 GB of RAM)
Now the problem is that we can't use pound to log the requests anymore
because the load would go to values as high as 10. Without logs we
have values up to 2.
Now the question is how can we optimize pound to use logging again?
Is Pound 2.0.4 faster in that manner? Or should we try to compile
Pound by ourselfs to get a bit more performance?
As logging backend we use syslog-ng on the same machine as pound
resides. It does not need much cpu power in our configuration (about
5-10%) but has to write about 6 to 8 GB of logs in 24 hours.
By the way: we can't use the backend servers to do the logging because
this makes some problems when we try to analyze our logs with awstats.

I really really hope that someone of you has a quite nice idea to help us.

--

Best wishes
Bernhard Grün

On Wed, 2006-05-03 at 10:47 +0200, Bernhard Grün wrote:[...]

Several answers here:

- Pound 2.0.4 with PCRE is significantly faster and more efficient than
older versions. This means less CPU load for the same workload, which
may help in your case.

- syslog is normally limited by disk rather than CPU (at least in my
experience). You should look at tuning options (such as not flushing the
output on every message - big win), better/faster disk access (HW) and
possibly remote logging (if you have some other disk-intensive
application on the same machine).

- you can very well run Pound without syslog - compile it to send
messages to stdout/stderr. A package like the DJB daemontools is very
helpful for these cases, and may help quite a bit with performance.

- finally you could reconsider back-end logs: Pound passes the original
client IP address in the X-Forwarded-for header, which could be logged
by your back-ends and later used by awstats.

Hope this helps some.[...]