hai gonzalo arana, thanks for detailed reply.
> Looks like you are running into a CPU bottleneck. Perhaps you may want > to add --enable-cpu-profiling to configure, and check cpu usage data > with cache manager, or compile and link with -pg and check results with > gprof. I have done configuration with --enable-cpu-profiling and monitoring with cachemgr.cgi script. > Also, verify whether CPU usage is in kernel-mode or user-mode with vmstat > during the test (sar gives this information as well). vmstat result when squid is running at peak load ( 180 req / sec ), procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu---- r b swpd free buff cache si so bi bo in cs us sy id wa 1 0 0 119024 34116 61252 0 0 0 110 11035 79 69 31 0 0 1 0 0 99464 34144 61256 0 0 0 148 13033 26 65 35 0 0 > > Looks like you are running with (the same?) CPU bottleneck. > > epoll's advantage is that CPU usage does not grow with the number of > idle TCP connections. If the number of concurrent connections is large, > and there are no idle connections, epoll should only give a small > increase in throughput (no cpu is used for traversing the list of fds). > > Is, by any chance, throughput (in bps) slightly larger with epoll? I did not get this. How to measure throughput (in bps)? > >> 008.75| Connection.cc:485: error: 1/1 (s110) Connection timed out >> 008.75| error: raw write after connect failed >> after these req / sec configuration setting. > > Try enabling SYN cookies, and running squid with ulimit -HSn 131072. I have tuned sysctl -w net.ipv4.tcp_syncookies=1, ulimit -HSn there. But I am getting same error reply as, Connection.cc:485: error: 1/1 (s110) Connection timed out can we get more req / sec satisfacation for 512 MB RAM, 927.753 MHz cpu (pIIII) ?? I am using /dev/null file system for benchmarking? Do you have benchmarking any results for squid? regards muthukumar