Heheh..."only" is a relative term. Our old 500 Mhz boxes couldn't even work two 7200 RPM IDE disks (on different buses, of course) effectively, and three provided a barely measurable boost. I'd be surprised if you aren't able to easily max your CPU with ReiserFS on a polygraph run on these boxes...and it will probably happen at around 110 reqs/sec., assuming reasonable configuration of kernel and Squid.
We currently get arount 70 reqs/sec using 25% CPU (5 minute average for both values) on this hardware. I'm confident that I'll get a pretty high number of requests/second through these proxies becase of the epoll patch.
Ah, yes, epoll could very well be an interesting twist...and it might make the relative filesystem results come out very differently.
