EBMS Tickets

I'm passing this on to you, Alan, since it's for importing.

This looks like a different error from the earlier one in OCEEBMS-121.

Doing some research, I see that it might possibly be a transient out-of-memory error that can occur when too much memory has been used up in a pool of memory shared by multiple applications. In our particular case, it might not even be EBMS that has the problem since I think there are a number of applications besides EBMS that are running on the same computer.

I'll do some more research and see if I can confirm that this is the problem. If it looks like it is, I'll report it to CBIIT, our server administration team, and ask them to increase the size of the memory pool that is running out. I don't think that should be hard for them to do.

If that's not the problem, maybe I'll find a different cause - though it's always hard to track down these transient errors that only occur once in a great while.

I'll do some more research.

I did some more research on this.  It's not a subject that I have
encountered before but, based on what I've learned from reading
questions, answers, and documentation on the web, I think the most
likely explanation is as follows:

The warning messages come from a caching package called "APC" for
"Alternative PHP Caching".  I found the messages in the source code for
that package.  It is a package of programs that hold our drupal scripts
in memory for faster execution.

The configuration file for APC on DEV (I can't look on PROD but it's
probably the same) indicates that there is one cache segment and it is
configured with 32 megabytes of memory.  That's the default
configuration for APC and, given that this error has only been reported
once, it's probably adequate for almost everything that we do, but the
system must have been very busy at the time the warnings appeared and
the limit was reached.  [Interestingly, the "INSTALL" file for APC
suggests setting the value to 128 megabytes.'

The warning does not indicate a crash or a bug and the program that was
running when it happened seems to continue running.

I therefore recommend that we ignore this for the time being, changing
the status to "On hold" or "Resolved - Won't fix".  If the warning
occurs more often in the future then I think we should ask CBIIT to
raise the amount of memory in the cache.  A small additional amount,
e.g., to a total of 48 MB, would probably be enough.


In case someone looks at this in the future, the APC configuration file
can be found here:

   /etc/php.d/apc.ini

Source code for APC is here:

   http://pecl.php.net/package/APC

Documentation for the entries in the file is here:

   http://php.net/manual/en/apc.configuration.php

There have been no reports of this problem in the almost 8 months since we put it on hold. I propose that we close the issue. If it does recur and becomes a nuisance, we know what to do - ask CBIIT to raise the size of the cache memory pool.

I think it's okay to close this one as well.

It's been over a year since this was reported, and it doesn't appear to have happened since. I am closing this, and we can re-open if it happens again.