Compacting mailboxes...

[Craig White]

On Thu, 2005-02-24 at 19:30 -0500, David G Mcmurtrie wrote:
> On Thu, 24 Feb 2005, Forrest Aldrich wrote:
> 
> > In any case, an issue was brought up whereby if a user doesn't "Compact"
> > their mailbox (done via most common MUA's like Thunderbird) the deleted
> > messages can linger - for however long.
> >
> > I've personally seen this before.
> 
> The IMAP protocol specifies this (check out RFC 3501).  IMAP utilizes a
> two stage delete model.  First a client must set the "Deleted" flag for a
> message, then the client must send an expunge command to the server.
> Until the expunge command is sent, the messages still exist but they're
> marked for deletion.  This isn't cyrus specific, it's how IMAP works.
> 
> The behavior you're observing is that when you tell your client to delete
> a message it's setting the Deleted flag.  When you tell your client to
> compact the folder, it's sending an expunge command.
> 
> > I'm concerned about disk space consumption of these messages in-limbo.
> > Is there some mechanism that can force a "compact" of the mailbox to
> > remove these deleted messages - or is there another method to manage
> > this scenario?
> 
> I don't know of a server-side way to do what you want.  That doesn't mean
> it can't be done, though.  I think what you really need to do is educate
> your users.  Clients vary greatly in how they work by default and how they
> allow you to configure them.  You should look for a client configuration
> option that will always send an expunge whenever a message is deleted.
----
indeed - expunge is a client function and as noted, standard IMAP
behavior by design. Most programs have various options for handling
deleted messages and Thunderbird (as op mentioned) clearly has many -
including 'clean up "expunge" on exit.'

Probably very important for op of a mail server to thoroughly
inspect/test how each mail client would interact with server so he can
field these questions or better yet, have a small web page to point
people to in order to direct them to optimizing their mail clients
interaction with the server.

There are some programs (horde/imp) comes to mind which do 'maintenance
procedures' that are as of a client but appear almost server like which
can do this as well but is pretty much out of bounds for this
discussion.

Craig

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