サーバーが多くのリクエストを受け取ると、php-fpm レコード (php5-fpm.log) は次のようになります。
WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 8 children, there are 0 idle, and 6 total children
私のphp-fpm.confは次のとおりです。
...
pm = dynamic
pm.max_children = 50
pm.start_servers = 2
pm.min_spare_servers = 1
pm.max_spare_servers = 3
pm.max_requests = 200
...