Re: Large spool mboxes => slow?

> Date: Thu, 9 Mar 2006 11:52:56 +0000 (WET)
> From: Hugh Sasse <[email protected]>
> To: Subscribers of Qpopper <[email protected]>
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> Subject: Large spool mboxes => slow?
> 
> We have several people who POP their mail fairly frequently, but
> they leave mail on the server.  These large files seem to be the
> main thing impacting the performance of the mail server.  Qpopper
> has no quota options as such, and some of the policy controls are
> dependent on being sure how the client interacts with the serveer,
> and I am not familiar with all the clients people use.
> The OS (Solaris9) has quotas for disks, but with this being for mail
> I'm presently unsure as to how that will impact on users.
> So, I have reached the conclusion that the best thing I can do to
> improve performance is to use the --enable-temp-drop-dir and point
> it to a different partition from /var/spool/mail so that disk seeks
> on both partitions may occur in parallel.  Does this sound like a

Point to different spindles on different I/O channels.  You have 
c0t0d0s6.  Use c1t0d0s6 for the temp-drop-dir.  At a minimum, point to 
different spindles.

any POP3 daemon is going to have problem is the spool gets too large.

Also enable server mode.  enable caching of temp dir

> useful thing to do?  What if they are on different slices of the same
> disk -- would that make things worse (further for the heads to seek)? 

This WILL make things worse for just the reason you've stated.

> Filesystem            kbytes    used   avail capacity  Mounted on
> /dev/dsk/c0t0d0s7    10525500 9733158  687087    94%    /export/home
> /dev/dsk/c0t0d0s3    4030014  373130 3616584    10%    /var
> 
> Is there anything else I can do to qpopper that will help?
> 
> Getting users to change their behaviour is another story altogether,
> of course :-)
> 
>         Hugh
> 
> 

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Gregory Hicks                           | Principal Systems Engineer
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