Hello Community Members,
We are running ubuntu 12.04. There are 103 PHP applications running on the same server. One application executes a command line php script for all the 103 applications. We saw a weird behavior, on the server we have 15GB ram out of which 14 GB was consumed by the apache user www-data. When our application user got active the server was very slow, almost unavailable. the htop shows that there are 637 processes for www-data in sleep mode. Further we restarted the cron server and killed all the www-data processes and the memory usage went to 705MB to 903MB.
we have checked syslog the oom killer woke up and tried to kill processes a lot of times.
Is there any way to find why all the processes was in sleep mode, what exactly was the process for which server was putting other process to sleep mode?