[ILUG] Linux SMP on Xeons

[John P. Looney (Kate)]

On Thu, Jun 15, 2000 at 09:27:34AM +0100, Colm Buckley mentioned:
> >>  Mail is I/O bound.
> >>  From a "# of cpus" point of view, probably over-spec.
> > Way, way over.
> Noted.  I might leave it as it is, though, to leave room for the system
> to grow.

 But won't that mean that you'll just get I/O bound. Much better to have
two or three single CPU machines relaying for you, and that way you get
much better redundancy too ?

> >> Make sure you have a separate, fast disk (goat type)
> > Goat type? Eh, what? I'm assuming that's a weird way of saying 10,000
> > RPM disk 8)
> Yep, that's a given.  I'm looking at 2 9GB 10k LVD drives, with some
> sort of RAID arrangement, ideally with a hardware RAID controller with
> NVRAM write cache, for the queue dir.  (Does anyone know of such a beast
> with Linux support?) ReiserFS seems like a good bet for this directory, too.

 With that much CPU, software raid is likely to be a lot faster...though
I've admittedly used only a few RAID cards, they just save CPU. For some
reason, Sun machines *never* use hardware RAID.

> > For the mail directories, (assuming they're on this machine in an
> > exported /var/mail or an IMAP server message store), I'd do mirrored
> > stripes if I had the disks, grudgingly settling for RAID5 if not.
> Not really an issue - almost all the mail in question is outgoing (the
> application is 'managed mailshots to a customer db').

 Ah. Spamfest. In that case, perhaps muliple mail machines isn't the best.
And more than a dual CPU isn't *really* needed...your biggest problem is
going to be filling the network pipe as fast as you can rip "to" addresses
from the database. And I've a feeling that even a PII 233 could fill a
2meg line with emails, if they all had similar bodies...

Kate

-- 
The words of the unwary are apt to cause needless pain and bloody violence.
                                                        - Zen Master Greg