I have a web application that is being migrated from Ubuntu 14.04 to Ubuntu 16.04. I have followed all of the instructions that I normally would have done for setting this up in 14.04. The application runs fine…as long as I don’t logout of my ssh session, I start to get these errors when I do:
(22)Invalid argument: Failed to acquire global mutex lock at index 7
I have mpm_prefork enabled, mpm_event is disabled. (My instructions do not mention mpm_worker, but it is disabled as well)
Apache is running as a local user (not www-data or root).
When I run
ipcs -s I see several semaphore arrays for this user. If I log out of my ssh session and log back in, those semaphores are gone. Coincidentally, if I start apache without logging in as that user, it works perfectly fine until someone logs in as that user and logs out.
I have confirmed that ipcrm is not being called when the semaphores are removed.