My friend asked me to check the server with this problem. I did and of course first I checked free space on disk using ‘df -h’, but free space was ok. Googling around I found the reason. Unclean shutdown of Apache left many semaphores opened. So, I cleaned them with
for i in `ipcs -s | awk '/nobody/ {print $2}'`; do (ipcrm -s $i); done
You should replace “nobody” in the command with the name of the user Apache is running on your system under. Also I increased semaphore limit in /etc/sysctl.conf by adding to the end of this file
kernel.msgmni = 1024 kernel.sem = 250 256000 32 1024
No system restart is needed to apply changes. Just issue 'sysctl -p‘ command. The solution was found here.
You may also want to switch to another SSLMutex implementation.
