Too slow

[Michael Loftis]

--On April 7, 2006 8:58:57 PM +0200 Sascha Bieler 
<sascha.bieler at radiogong.de> wrote:

> Hi  there,
>
> I am running cyrus-imapd-2.1.12 on  a Gentoo Linux with kernel 2.6.15.
>
> Got a Pentium 4 Xeon 2,8 GHz and 2 GB Ram. The cyruspartition is ext3 on a
> SCSI RAID 5.
>
> hdparm -tT /dev/sda says:
>
> /dev/sda:
>  Timing cached reads:   2316 MB in  2.00 seconds = 1158.00 MB/sec
>  Timing buffered disk reads:   80 MB in  3.01 seconds =  26.58 MB/sec
>
>
>
> Everythings working just fine, but when I want to delete an email it's
> sooooo slowly...
>
> Has anyone a hint for me?

Depends a LOT on your I/O load.  27MB/sec is pretty slow, and that's reads, 
RAID5 writes are often as slow as half, depending on your hardware, plus 
that's before the filesystem is in the way.  Large directories slow ext3 
down quite a bit.

Expunge operations on our large mail backends are often pretty slow too, 
but aren't too bad, though we're using a lot bigger hardware and servers.