Re: header caching

[Thomas Glanzmann <sithglan@xxxxxxxxxxxxxxxxxxxx>]

Hello,

> I have my shell account at Panix, and they are moving all accounts
> over from mbox to maildir.  Problem is that a mail folder I use a lot
> has over 2000 messages, and it's usually REALLY slow to load the
> mailbox.  I can see it slowly counting up, where with mbox it's pretty
> fast.  I said that I can't take it like this, but they said that they
> will be installing a new version of mutt using header caching.  Is
> there any offical documentation around on this so I can figure it out?
> I run my own patched version of mutt, so I will need to build it
> myself.  I currently run 1.4.2i.

With mutt-1.5.9 you need the following patch to support maildir header
caching:

http://wwwcip.informatik.uni-erlangen.de/~sithglan/mutt/mutt-cvs-header-cache.29

But the  best way is to simply use CVS HEAD which has the patch already
included. I think that tlr will release mutt-1.5.10 this weekend. And
this time really.

> Would this hcache directory take up a lot of disk space?

TLR will commit today (as soon as I send him the patch) qdbm database
backend support for hcache. This makes it possible to compress the
header cache database without loosing much time on the initial opening:

The relevant options are documented in
http://dev.mutt.org/doc/manual.txt section 6.3.101 and counting. The
documentation is updated every 30 minutes. So the new option for
compression when compiled with qdbm support will be there.

A few numbers from praxis:

        (faui03) [/tmp/sithglan-hcache] ls -1Shlr | tail -1
        -rw-------    1 sithglan icipguru     5.0M Jul 28 09:19 
b2932362d26987e33bd5b9ec9653758b
        (faui03) [/tmp/sithglan-hcache] du -sh
        19M     .

I have one cache file per mailbox configured. And my biggest mailbox
with 34312 messages takes up 5 megabyte diskspace. 

        (faui03) [~] rm /tmp/sithglan-hcache/*
        (faui03) [~] time 
/home/cip/adm/sithglan/work/mutt/git.old/mutt-tg-solaris/mutt -f =.lists.uml -e 
'exec exit'

        real    0m54.881s
        user    0m12.900s
        sys     0m8.180s
        (faui03) [~] !!
        time /home/cip/adm/sithglan/work/mutt/git.old/mutt-tg-solaris/mutt -f 
=.lists.uml -e 'exec exit'

        real    0m4.498s
        user    0m4.090s
        sys     0m0.320s

As you can see the initial caching takes 55 seconds to fill up the cache
database. And 5 Seconds on conscetuive opens of the already cached
database.

        Thomas