My php fpm process gives me the following warning:
[29-Apr-2014 13:06:10] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 8 children, there are 19 idle, and 51 total children [29-Apr-2014 13:07:09] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 8 children, there are 14 idle, and 47 total children [29-Apr-2014 13:07:10] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 16 children, there are 17 idle, and 53 total children [29-Apr-2014 13:07:11] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 32 children, there are 14 idle, and 56 total children [29-Apr-2014 13:07:12] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 32 children, there are 19 idle, and 62 total children [29-Apr-2014 13:07:13] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 32 children, there are 18 idle, and 63 total children [29-Apr-2014 13:07:14] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 32 children, there are 19 idle, and 65 total children [29-Apr-2014 13:07:15] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 32 children, there are 18 idle, and 66 total children [29-Apr-2014 13:07:16] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 32 children, there are 16 idle, and 68 total children [29-Apr-2014 13:07:23] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 8 children, there are 14 idle, and 80 total children [29-Apr-2014 13:07:24] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 16 children, there are 19 idle, and 86 total children [29-Apr-2014 13:07:25] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 32 children, there are 19 idle, and 87 total children
My fpm.conf is :
pm.max_children = 161
pm.start_servers = 20
pm.min_spare_servers = 20
pm.max_spare_servers = 40
pm.max_requests = 1000
My questions are
why are children being spawned even if I am not reaching the max_children value? Is it because of extra traffic and because the idle children need to reach the minimum of 20 they can not be used up?
Is this creating an overhead on my system?