Performance on 64 bit Linux vs 32 Bit

[Glenn Steen]

On 23/10/2007, ram <ram at netcore.co.in> wrote:
> On Tue, 2007-10-23 at 10:15 +0100, Randal, Phil wrote:
> > We're running it fine here on 64-bit CentOS 5.
> >
> > Dell 2950, 4GB RAM, quad-core Xeon, mirrored hard disks.
> >
> > Using a 64-bit build of McAfee's uvscan along with ClamAV.
> >
> > Cheers,
> >
> > Phil
> >
>
> On 32-bit Centos 4.4 ( 4GB Ram , 2 x dual core Xeons )
> We get upto 20-35k mails hitting the server per hour
>
>
> We run caching DNS and rbldns zones for most "rsyncable" DNS lists for
> SA ( spamhaus , dsbl , dnswl , sorbs surbl etc )
> Most connections , around 85% , get rejected by RBL checks at postfix.
>
> The rest of the mails get scanned with nearly 3-5 minutes delay. Though
> sometimes it oddly takes longer
>
> Can this be improved by upgrade to 64-bit. This is what I am looking
> for
>
> Thanks
> Ram

That would depend on where your bottlenecks, if any, are... Likely not
the "magic bullet" you're looking for though. Since Phil runs uvscan
and clamav in 64-bit... He might be able to tell us if there is any
measurable difference between a 32-bit and 64-bit incarnation of those
two.
With the incoming volume you cite, I imagine anything will make a
noticeable difference... Heck, the fork/exec time of uvscan would
probably be a problem:-).
As with any performance tuning... the data you don't have to handle is
better than handling data fast ... But I assume you've done what can
be done to reduce the incoming volume before rbls...

Cheers
-- 
-- Glenn
email: glenn < dot > steen < at > gmail < dot > com
work: glenn < dot > steen < at > ap1 < dot > se