To split the hairs a bit further, squid's core is mostly single threaded, but does have disk i/o processes that are spawned out. So going from single to dual core will give you gains for that reason in addition to the benefit of other system processes no longer competing with squid for timeslices. That said, due to the single-threaded core, there are diminishing returns in going to quad CPUs or greater when running a single instance of squid, unless you have helper processes (rewriters, auth helpers, etc) which consume lots of cpu. At my last company we solved that scaling issue by simply running multiple squids on each server (There's even a nifty hack to bind them all to port 80 at the same time so you don't need multiple IP addresses - search the archives for it). -C On Apr 25, 2010, at 7:32 PM, Amos Jeffries wrote: > On Sun, 25 Apr 2010 16:47:02 -0500, Matt <lm7812@xxxxxxxxx> wrote: >> Will Squid benefit much from moving to a dual core CPU? Currently I >> have it running on a single core 1.8ghz socket 775 with 8g of ram on >> centos 5.x 64 bit. Also, is there a way to tell squid to do most of >> its cache clean up during the off peak hours of like 1am to 6am? >> >> Matt > > Yes. Dual-core boxes can offer a whole CPU to Squid while leaving the > other for system and other background things which would otherwise compete > with Squid for time. > > As for timing of the cache cleanup; no you can't set particular > time-of-day for it. When the overload thresholds kick in they really need > to be run right then. The regular maintenance garbaging cycle can be tunned > to happen more or less often as suits you. > > Amos >
