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Squid on SMP
Running Squid on true SMP machines is quite inefficient. When examining Ganglia, it is clear that most Kennisnet Squids flat out at 50% CPU usage, so basicly one CPU is being wasted. The same will probably be true with the Yahoo cluster, when it gets a heavy load.
Varnish as an alternative?
The Norwegian newspaper had 10 squids in their service, but decided that this was inefficient. They therefore sponsored the development of Varnish, a modern alternative to Squid that among other things can utilize SMP machines. The new system is in production, and apparently they reduced their need to 1 server plus backup, plus giving faster response times (It's just a feeling, but I think I've noticed this myself).
I don't know much about this stuff myself, but if such large reduction in servers are possible, this should be considered as a serious alternative to Squid for Wikimedia. -- Larsivi 09:19, 17 November 2006 (PST)
- Just noticed from recent changes that someone is already playing with it on Hawthorn :) -- Larsivi 09:25, 17 November 2006 (PST)