Re: Memory usage

* Daniel P. Berrange ([email protected]) [040312 12:56]:
> On Fri, Mar 12, 2004 at 12:18:05PM +0100, Mark Overmeer wrote:
> > * Daniel P. Berrange ([email protected]) [040312 12:13]:
> > > I've had a problem with memory usage too - I reduced memory consumption by 
> > > calling $message->destruct after finishing dealing with each message - but 
> > > I still can't process all 500MB of mail archives in one go without 
> > > restarting my script.
> > 
> > It would be nice to know why destruct() doesn't help.  Might be a
> > simple case of some final reference to be cleaned-up.  At the same
> > time, it may as well be cause by Perl trashing memory or other
> > memory leaks.  Various versions of Perl have memory leaks.
> 
> Could it be the Mail::Box::Manager object holding references to
> the Mail::Box objects - I currently just assume $manager->close 
> will cause all remaining references to the folder & thus its memory
> to be released ? I never hold any references to objects which
> aren't scoped to a short code block - my code basically looks like:

The situation is a little more complex.  The manager holds mailboxes,
and each mailbox holds messages, and the messages a header and a body.
Multipart and nested bodys hold list of bodies.

But at the same time, each of these objects refer back to their
parent, for instance: the body refers to its message.  For garbage
collection to work, the references "back" are weak references
(see Scalar::Util::weaken()).

In case I have forgotten to weaken one reference, somewhere, some
parts of the data structure may be kept alive, even after a descruct().
This is close to impossible to debug...
-- 
               MarkOv

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drs Mark A.C.J. Overmeer                                MARKOV Solutions
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