Re: [ARSCLIST] Hyperthreading (was Software for Mac)

[Rob Poretti <r.poretti@xxxxxxxxxxxx>]

Here is a good kb article on the basics of hyper-threading, multi-threading,
and multi-processing from Steinberg...

http://knowledgebase.steinberg.net/71_1.html

Cheers!

_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
Rob Poretti
Sales Engineer - Archiving
Cube-Tec North America
Vox.905.827.0741
Fax.905.901.9996
Cel.905-510.6785
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/


-----Original Message-----
From: Association for Recorded Sound Discussion List
[mailto:ARSCLIST@xxxxxxx] On Behalf Of Richard L. Hess
Sent: October 18, 2008 2:05 PM
To: ARSCLIST@xxxxxxxxxxxxxxxx
Subject: Re: [ARSCLIST] Hyperthreading (was Software for Mac)

At 11:48 PM 2008-10-17, carlstephen koto wrote:

>Thanks Steven, that's why I asked Richard about the hyperthreading
>before. I use a quad cored Mac (each processor is 2.6G) and when I'm
>processing audio, I open a widget that displays processor usage. When
>I run my restoration software (iZotope Rx) or any other intensive
>editing processes, only one of the four processors is doing 90% (just
>a visual estimate) of the work. If the one processor is "limiting
>out" a second processor will momentarily run up to about 50%.The
>other three are barely working (running the display and operating
>system?).  As a result, my software runs just a little faster than it
>would on a single processor.

Hello, Steve,

That was what I saw in the hyperthreading model as well under 
Windows. Alas, in hyperthreading, it appears that half the CPU cycles 
are allocated to each thread (as opposed to the multi-core 
processors), therefore in hyperthreading, I was losing performance 
with this function activated.

Your report on what the Mac does and what I've seen hyperthreading do 
under Windows are why I've been staying away from multi-core CPUs 
which have a big cost with little benefit IN THIS APPLICATION. In 
fact, I might suggest that other than efficiencies in fewer CPU clock 
cycles per instruction in the latest processors, that the typical 
mid-2.5 GHz multi-core processor may not offer any improvement over a 
3 GHz single core unit.

It would be interesting to see further data points on this.

Cheers,

Richard

Richard L. Hess                   email: richard@xxxxxxxxxxxxxxx
Aurora, Ontario, Canada       (905) 713 6733     1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.