We are currently using squid set up as a reverse proxy to accelerate several heavy backends (mod_perl, etc) and to protect them from slow client connections.
I am looking into replacing the squid with apache+mod_proxy. Why? Because ultimately I'd like to be able to cluster the frontend using mod_backhand + wackamole. The primary reason for clustering isn't for load-balancing (yet) but for failover handling. So, ideally, one machine should be enough to serve the whole server load. Speaking of load, the squid (2.3.STABLE1) is currently doing up to 80 requests per second at a cache hit ratio of around 72%. This is on one box, a Dual 500MHz Pentium III with 1GB RAM. Average object size is 6KB. 200/304 ratio is around 5/3. Now, I've tried to replace the squid with apache+mod_proxy (1.3.11) and the frontend very quickly came to a standstill. I set MaxClients to 256 but all slots filled up fast. I upped MaxClients to 512 (recompiled with patched httpd.h) but the result was the same. All slots were occupied in no time and the server ground to a halt. Now I'm left with two choices: give up or try harder :-) Before I decide for one of them I thought I'd ask on the lists (sorry for the x-post) to see if the above numbers (80 Hits/Second) are in fact feasible with apache/mod_proxy on one box. Are there any benchmarks around? Does someone have a similar setup and how many requests can they serve? Should I up MaxClients any further? Will I get better results using a newer version of apache? Or should I give up and stick with squid? TIA for your input.
