can you help me find the bottle neck on my server. In the previous question I asked on SF, I was told that memory is no problem and I have plenty of it.
I'm curious about CPU, perhaps HDs ... what could stop me from serving double the amount of the hits, should my users increase?
do I need to do some sort of httpd.conf optimization? or php.ini optimization?
server: 16 GB DDR3-RAM ECC HDD RAID1, 2x 250 GB SATA II-HDD 7.200 rpm 2 additional 80 GB SSDs CPU 2x Intel Xeon E5520 Quadcore
software: php 5.3.6 mysql 5.5 apache 2.2.3 centos 5.5, 2.6.18-238.12.1.el5 #1 SMP Tue May 31 13:22:04 EDT 2011 x86_64 x86_64 x86_64 GNU/Linux
current off peak hour top:
top - 16:46:17 up 2 days, 14:57, 4 users, load average: 4.22, 3.53, 3.19
Tasks: 305 total, 4 running, 300 sleeping, 0 stopped, 1 zombie
Cpu(s): 19.1%us, 11.1%sy, 0.0%ni, 69.6%id, 0.1%wa, 0.0%hi, 0.1%si, 0.0%st
Mem: 16427200k total, 16280100k used, 147100k free, 3131684k buffers
Swap: 2104496k total, 268k used, 2104228k free, 6221860k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
20157 apache 15 0 387m 67m 4088 S 57.5 0.4 0:21.00 httpd
4106 apache 20 0 389m 67m 5164 R 40.9 0.4 0:59.57 httpd
20156 apache 15 0 357m 35m 5072 S 33.9 0.2 0:24.82 httpd
20148 apache 18 0 357m 35m 5052 R 31.2 0.2 0:25.00 httpd
1759 apache 15 0 391m 69m 5188 S 29.9 0.4 4:37.24 httpd
16194 apache 18 0 358m 36m 5192 S 28.9 0.2 3:44.69 httpd
20147 apache 16 0 357m 35m 5148 S 23.6 0.2 0:26.73 httpd
17329 apache 15 0 370m 48m 5188 S 15.0 0.3 2:13.67 httpd
20140 apache 15 0 359m 37m 5136 S 8.0 0.2 0:20.53 httpd
28473 apache 15 0 358m 36m 5172 S 4.0 0.2 1:20.78 httpd
20158 apache 15 0 357m 35m 5112 S 3.7 0.2 0:22.96 httpd
26922 apache 15 0 357m 36m 5840 R 2.3 0.2 2:22.49 httpd
26925 apache 15 0 358m 36m 5188 S 2.3 0.2 1:28.63 httpd
12642 apache 15 0 357m 35m 5076 S 1.7 0.2 0:40.92 httpd
17963 apache 15 0 357m 35m 5152 S 1.7 0.2 0:27.35 httpd
2687 apache 15 0 358m 36m 5192 S 1.0 0.2 4:28.17 httpd
4419 mysql 15 0 668m 175m 7204 S 1.0 1.1 4:07.99 mysqld
20155 apache 16 0 368m 46m 5144 S 1.0 0.3 0:16.67 httpd
26923 apache 17 0 387m 66m 5168 S 1.0 0.4 1:42.18 httpd
1277 apache 15 0 355m 34m 3988 S 0.7 0.2 0:11.11 httpd
3571 root 16 0 13400 1792 848 S 0.3 0.0 3:03.17 top
32204 root 15 0 90156 3404 2648 S 0.3 0.0 0:00.19 sshd
1 root 15 0 10372 680 572 S 0.0 0.0 0:02.04 init