The system is running ubuntu 10.04, running Apache/2.2.14 (Ubuntu)
It happened today where I noticed the server was extremely unresponsive (took 5+ minutes to log into SSH). Upon viewing the system resouces, it was obvious that Apache was the culprit (with 150 processes open), and I turned Apache off so I was able to work.
Looking at the error log, I found this
[Tue Jul 26 11:55:33 2011] [error] server reached MaxClients setting, consider raising the MaxClients setting [Tue Jul 26 12:49:56 2011] [warn] child process 4814 still did not exit, sending a SIGTERM [Tue Jul 26 12:49:58 2011] [warn] child process 4814 still did not exit, sending a SIGTERM [Tue Jul 26 12:50:00 2011] [warn] child process 4814 still did not exit, sending a SIGTERM [Tue Jul 26 12:50:02 2011] [error] child process 4814 still did not exit, sending a SIGKILL [Tue Jul 26 12:50:03 2011] [error] could not make child process 4814 exit, attempting to continue anyway
These errors were appearing for about 150 different PID's (I just pulled these out for clairity).
I have the following mods enabled
alias.conf authz_default.load autoindex.conf deflate.load mime.conf php5.conf rewrite.load ssl.load alias.load authz_groupfile.load autoindex.load dir.conf mime.load php5.load setenvif.conf status.conf auth_basic.load authz_host.load cgi.load dir.load negotiation.conf reqtimeout.conf setenvif.load status.load authn_file.load authz_user.load deflate.conf env.load negotiation.load reqtimeout.load ssl.conf
I obviously would not like a repeat of this issue, and would like some insight as to what happened, and how to prevent it.
EDIT: Around the time of the issue occuring, the access log shows the requests being relativly light (a request or 2 every few seconds), and even then the requests were very lightweight.