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From: Jan Simon on 3 Jun 2010 10:56
Dear Walter!

> > The users says he doesn't use MEX functions but is using the report
> > generator. Assuming that uses MEX functions.
> > I'll read up on the profiler and see if that sheds any light.
>
> Is it possible that the user's system does not have especially much RAM
> and that Matlab is exceeding the physical RAM and this is using the
> system swap file? Swapping to disk is very slow, and can result in the
> kinds of behaviour you report.

Of course, the profiler is the best idea!

If the problem is caused by disk swapping of virtual memory, the problem should disappear after some minutes.

"The users says" is usually no good indicator. The user always says, that he/she has not changed anything before the problem occures, or at least "nothing important". :-)
[M, Mex, J] = inmem
tells more exactly which Mex and Java functions have been called...

Good luck, Jan
From: Walter Roberson on 3 Jun 2010 14:41
Jan Simon wrote:

> If the problem is caused by disk swapping of virtual memory, the problem
> should disappear after some minutes.

It is not uncommon for programs to continue to have swapping problems once
they start, as memory fragmentation can make it difficult to find enough
contiguous memory; that and once you start using really large arrays, they
tend to be copied around.

I don't think I've done anything really big in Matlab; in another package I've
used, the server starts to respond fairly slowly once I read 10.5 Gb of
memory, and the server effectively dies when the package asks for more than
13.5 Gb of memory. When I run that package on my desktop (2Gb of RAM) and
exhaust the swap file, the result is to take my desktop down to the point of
only responding to ping and nothing else (not even mouse movement, no disk
activity... deadlocked!)
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