Hi,--On 6. Januar 2006 12:47:49 +0100 Paul Dekkers <[EMAIL PROTECTED]> wrote:
We are about to move our mail to a different machine, running a different OS and a different filesystem (ext3, since that is "the one" for RH).
that's why we use it as well. We started with XFS, but then Red Hat wouldn't give us support. Anyway, with RHEL 3 we are quite happy with the performance.
While thinking about this filesystem for use with cyrus, I was wondering if it would do any good to split up the current mailspool in different imap partitions. I'm curious what others would do. I've searched the archive a bit, but for now it seems people are only partitioning for expanding storage... Currently there are about 7000000 files, split over 14000 mailfolders, consuming 250 gigabyes, for about 80 users.
Wow, that's a lot of mail for so few users! We have 40,000 users and 266 gigabytes of mail ...
(Large part of it is a shared archive, a few have large user boxes.) Everything is on one partition now. Does it (filesystem / safety / recovery / performance-wise) make sense to use different partitions, maybe about 100G large, and spread archive and users over 3 or 4 partitions, or would you people rather put everything in a single partition instead? I have about 1 terabyte available (managed with lvm).
I've thought about that as well, but have decided against it. Having to juggle partitions increases the complexity. The only real downside to large partitions is disaster recovery and we feel we have that covered. Our SAN is capable of "flash copies" and according to estimations we can recover within about two hours. Hasn't yet been tested, though ;-)
I think about not enabling dir_index on ext3 after discovering that this dramatically _decreases_ read-performance, so in that perspective this might keep the filesystem tables more clean and keeps down fragmentation? But if someone tells me that this really doesn't matter then I can as well keep everything in one partition: I don't see myself as a filesystem expert ;-)
Neither am I. We mount "-o noatime", that's it.
P.S. Initially I want to make filesystem-snapshots and rsync the data to a different mailserver as sort of "hot standby". (Snapshots might be interesting for partitioning.) Later on we'll be using 2.3 and the replication code, after we did some more testing with that. But then we'd drop the redhat package too, and with that the support from redhat - I assume?
We don't use Red Hat's RPM, but the Invoca one. We never needed support for Cyrus, only for OS related things.
Does anyone have experience with the redhat support on cyrus? (Is it worth running 2.2 for instead of 2.3? ;-))
I don't think so. IMO the support is spotty at best, anyway. I really doubt it will be much better for Cyrus.
Cheers, Sebastian -- Sebastian Hagedorn - RZKR-R1 (Gebäude 52), Zimmer 18 Zentrum für angewandte Informatik - Universitätsweiter Service RRZK Universität zu Köln / Cologne University - Tel. +49-221-478-5587 Skype: shagedorn
pgp1n2q8q6LVD.pgp
Description: PGP signature
---- Cyrus Home Page: http://asg.web.cmu.edu/cyrus Cyrus Wiki/FAQ: http://cyruswiki.andrew.cmu.edu List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html
