Re: [exim] HArdware Suggestions for exim courier-imap

Αρχική Σελίδα
Delete this message
Reply to this message
Συντάκτης: Marc Perkel
Ημερομηνία:  
Προς: Chris Meadors
Υ/ο: exim-users
Αντικείμενο: Re: [exim] HArdware Suggestions for exim courier-imap


Chris Meadors wrote:

>On Tue, 2005-08-16 at 07:46 -0700, Marc Perkel wrote:
>
>
>>A few quick thought. You can never have too much ram. As to raid, I'd
>>just use Raid 1 - it's faster than raid 5. If you're running Linux I
>>like the reiser file system for email because it has unlimited inodes.
>>As to CPU - if you are running spam filtering especially spamassassin
>>the good fast processing helps. If you want to save money I think the
>>new dual core Athlons from AMD would be very cost effective.
>>
>>
>
>RAID 1 is faster if you don't have the CPU. But with a hardware RAID
>card, or basically any CPU made in the last five years, you should have
>enough power to perform the xor calculations needed to distribute the
>parity blocks. The RAID 1 is faster with reads, as they can be spread
>across the drives. But when writing to a RAID 1 array all data must hit
>all drives, so you are only as fast as the slowest drive in the array
>(most people just use two or three of the same drive, but still you are
>limited to the speed of that drive). With RAID 5 reads and writes are
>distributed across multiple drives. The more drives in the array the
>better the performance (up to the speed of the bus). There is an
>additional overhead of the parity data but it is minimal.
>
>
>

Yes - that's true. But I'm thinking in terms of how much power you get
at the lowest price. If money isn't a problem then hardware raid scsi is
the way to go.
I'm just not that rich myself. So the less expensive alternative would
be something like raid 1 and a couple of 250 gig SATA drives. But you
may be right in that Raid 5 controllers aren't that expensive.

--
Marc Perkel - marc@???

Spam Filter: http://www.junkemailfilter.com
    My Blog: http://marc.perkel.com