On Wed, Aug 22, 2007, rahul wrote: > [Jyri Virkki:] > | > and it has a link to the Squid Feature poll that has been setup. > | > http://vrthra.googlepages.com/squidpoll.html > | > | I'm surprised some of these (like logging) must be chosen at > | compile-time, that's quite limiting. > > If the logging is disabled during compile time, It is removed completely > from the Request Path. (Introducing no overhead at all). While even if > the logging is enabled during compile time, The administrator can > disable it from the squid.conf file. (With a --possibly small -- overhead > for checking the squid.conf option)
Ah, squid performance discussions. :) Logging itself isn't high overhead. The fact squid-2.6 and Squid-3 right now log using stdio in the same single-threaded process is the problem if administrators -wanted- to keep logs. I've written some proof of concept code (s26_logfile_daemon branch at squid.sf.net) which breaks out logfile writing to an external process. If you want to know where the CPU is hiding then grab a copy of polygraph (http://www.web-polygraph.org/), configure a client/server, setup a Squid proxy server, run the Polymix-4 test suite and do some Squid profiling. My s26_logfile_daemon branch removes stdio logfile writes as a bottleneck (around a couple hundred requests a second with stdio; up to a few thousand a second..) but the Squid bottlenecks are elsewhere.. :) (don't forget to compile squid-2.6 with --enable-dev-poll either.) adrian
