Mail archiving

[David Gibson]

On Thu, Sep 05, 2002 at 03:08:29PM +1000, Matthew Hawkins wrote:
> Martijn van Oosterhout (kleptog at svana.org) wrote:
> > Hi,
> > 
> > As everyone knows, mutt doesn't handle large mailboxes very well (at least
> 
> Strange, I've had mutt open a 50,000+ message bugtraq mbox with no
> problems.  What you might like to do is increase the size of $read_inc
> and $write_inc (from memory).  This can be done on a per-mailbox basis
> with hooks if you don't want to make the changes global.
> 
> With the default settings, mutt will spend too much time updating the
> display and not enough parsing the mailbox.
> 
> If you want to see an MUA that truly is notoriously bad at handling
> large mailboxes, run Pine.  It loads each mailbox into memory,
> completely (I think it mmaps it).  So if you have a 400Mb mailbox,
> you'll need at least 400Mb of ram or Pine will lock the system up.  Been
> there, done that :-)

Um... if reading a 400MB file via mmap() causes a crash, something is
very wrong:  the mmap() itself won't take any (physical) memory it
just maps the file into virtual memory.  As pine reads pages they will
be faulted into RAM, but as it moves further on in the file, the VM
should be able to drop the pages early in the mapping (if they're
accessed again they can always be refetched from the file).

Of course there have been a lot of VM problems in recent times...

It is an inherent problem with mbox that there's essentially no way to
produce a message list without reading the entire file.

-- 
David Gibson			| For every complex problem there is a
david at gibson.dropbear.id.au	| solution which is simple, neat and
				| wrong.
http://www.ozlabs.org/people/dgibson