Hello, try setting client_persistent_connections off This will dramatically reduce the number of open fds and reduce the amount of processor time of squid. Greetings, Martin Stolle ekom21 -----Ursprüngliche Nachricht----- Von: Joost de Heer [mailto:sanguis@xxxxxxxxx] Gesendet: Montag, 17. Juli 2006 12:34 An: squid-users@xxxxxxxxxxxxxxx Betreff: Performance problems Hello, For a while, we've been having performance problems on one of our proxies. So far it looks like the machine is responding horridly when memory is freed. Here's some sample output from vmstat: 20060717-120000 2 3 0 18332 190544 1013220 1 1 0 3 0 0 2 2 1 1 20060717-120100 2 0 0 20744 191040 1014308 1 1 0 3 0 0 2 2 1 1 20060717-120200 2 0 0 20620 191576 1013444 1 1 0 3 0 0 2 2 1 1 20060717-120300 2 0 0 20828 192012 1012816 1 1 0 3 0 0 2 2 1 1 20060717-120400 1 0 0 29832 192392 1002868 1 1 0 3 0 0 2 2 1 1 20060717-120500 1 0 0 58108 192524 971760 1 1 0 3 0 0 2 2 1 1 20060717-120600 2 0 0 69172 192784 965056 1 1 0 3 0 0 2 2 1 1 20060717-120700 2 0 0 45644 193200 988184 1 1 0 3 0 0 2 2 1 1 20060717-120800 2 0 0 24668 193604 1008776 1 1 0 3 0 0 2 2 1 1 20060717-120900 2 0 0 21576 194048 1011436 1 1 0 3 0 0 2 2 1 1 20060717-121001 4 0 0 18056 194400 1010904 1 1 0 3 0 0 2 2 1 1 20060717-121100 2 0 0 18652 194904 1013504 1 1 0 3 0 0 2 2 1 1 Between 12:04 and 12:07, the machine was responding very poorly. Output of 'free': total used free shared buffers cached Mem: 2055448 2034576 20872 0 202756 1002868 -/+ buffers/cache: 828952 1226496 Swap: 8388600 0 8388600 Specs of the machine: Dual processor Intel(R) Xeon(TM) CPU 3.20GHz, 2 GB memory, machine has 3 HD's: 2x72.8GB mirror for OS/software/logs and 1x72.8G single disk for cache. OS: Linux kslh086 2.4.21-37.ELsmp #1 SMP Wed Sep 7 13:28:55 EDT 2005 i686 i686 i386 GNU/Linux (upgrade to 2.6 is unfortunately not possible) Disks are all ext3. Relevant squid.conf lines: cache_replacement_policy heap GDSF memory_replacement_policy heap GDSF memory_pools off cache_swap_low 90 cache_swap_high 95 maximum_object_size 64 KB maximum_object_size_in_memory 8 KB Apart from squid, Apache httpd 2.2.2 and BIND 9.3.2 (as a caching DNS server) are running on this machine. Relevant Apache config: MinSpareServers 5 MaxSpareServers 5 StartServers 5 MaxRequestsPerChild 0 MaxClients 5 I've already minimised the cache (it's only 1G large now) to see if the problem was too much disk access, but no luck. Normal cache usage is about 300-350 req/s, throughput is about 2.5MB/s, and usually there are about 2000-2500 fd's open (proxy is configured to run with 8192 available fd's, we can't lower this as the peak usage seems to be about 6000 fds) Anyone has any ideas what might cause this? Directions to search for? Joost
