64bit CPUs

[Eric Anderson]

Mariusz Grad wrote:
> Mike Tancsa:
> 
>>A somewhat obvious question to some perhaps, but what server application 
>>mix on FreeBSD today sees an improvement using 64bit CPUs ?  In my ISP 
>>centric world, my big apps are BIND, IMAP/POP3, httpd via apache, SMTP, AV 
>>and SPAM scanning, and firewalls/routing.  Apart from larger RAM, why would 
>>these benefit from the 64bit world ?  Or would they ?
> 
> Benefits from AMD64:
> - larger RAM limit (40bit memory address),
> - 64bit GRPs,
> - much faster access to memory (memory controller inside core - no northbridge),
> - it much better scales (with many CPUs) (he doesnt share memory bandwith),
> - large caches L1 = 64KB, L2 = 1MB (comparing to xeon 12/512K),

Some Xeon's have 2MB now..

> - DEP = Data Execution Protection (it has to be supported via OS),

Intel has the 'NX' (no execute) bit - isn't this the same?

> - Multimedia Extensions for graphics / vector processing.

Xeon's have this too I believe (I don't think this is anything new either).

> = Opterons remove memory bottlenecks espacially with multi-cpus.
> 
> Ive had large acceleration at:
> - math computation (f77, 2-4GB double precision matrix) single opteron 1.8GHz (sun v20z) was 4x faster then celeron 2.4GHz.
> - databases (pgsql) Opteron 1.8 GHz 2x faster then Xeon 3.2

That's interesting, although I wouldn't compare a Celeron against an 
AMD64, but interesting nonetheless.

> I would assume that everything which can run:
> - in parallel,
> - on multi-Opterons CPU,
> - which uses heavly RAM,
> - which can take benefits from 64bit registers (floating points),
> will have _extreamly_ boost comparing to Intels EMT64 (or Itanium2).

Agreed..

Eric



-- 
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Eric Anderson        Sr. Systems Administrator        Centaur Technology
A lost ounce of gold may be found, a lost moment of time never.
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