****3.3 6-core instances

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****3.3 6-core instances

I'm getting my new machine soon and eager to try some tests...just wondering...in a quick cluster, what do you guys recommend?

I hear it's best to use about 1/3 of the instances.

With my quadcore, I used 6 out of the 8 and that seemed the best.

Any thoughts?

PowerBook (my first baby!), 17" MacBook Pro 2.6ghz, 4gbRAM, Mac OS X (10.5.6)

Posted on Nov 29, 2010 4:45 PM

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Answer 1

Nov 29, 2010 4:52 PM in response to AppleUsur

You appear to be the only one capable of discussing this topic. You are babbling nonsense as far as I am concerned.

Are you talking about disabling some of the processors? Why in the world would you do that? You paid for them, why not use them? What makes you think you should shut some of them off?

Can you supply a bit more context?
What work do you do, what programs do you run, how large are your files?

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Answer 2

AppleUsur Author

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Nov 29, 2010 5:34 PM in response to Grant Bennet-Alder

I apologize for not being more clear. You must have no experience with the amount of instances you set in a Quick Cluster.

A year or so ago, there was much discussion on setting the amount of instances to make better use of your cores. In my case, using 6 out of 8 instances for a quad core had the best results when using Compressor. Some people liked using 4 out of 8.

That's what I'm babbling about.

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Answer 3

Nov 29, 2010 6:55 PM in response to AppleUsur

Over in the Compressor forum, they still seem to be talking about that.

Apple.com > Support > Discussions > Final Cut Studio > Compressor

One thread provided a link that went immediately into how many Instances are the right number for the Nehalem and Westmere processors that use HyperThreading to simulate twice the number of cores:

http://www.digitalrebellion.com/blog/posts/usingcompressor_with_multiplecores.html

It seems like their thinking is to use 12 for a 6-core, or possibly 11.

All this is to get around the single-threaded problem in Compressor, right?
Can this technology be used for any other problems, or is it tightly bound to Compressor?
And is this better or worse or different from setting up an XGrid to work on these problems?

Message was edited by: Grant Bennet-Alder

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Answer 4

AppleUsur Author

Level 1

5 points

Nov 29, 2010 10:30 PM in response to Grant Bennet-Alder

Thanks for the links.

Yes...for Compressor it's for getting the most out of your cores.

However, you can't export out of FCP and use them. You need to set up a QuickCluster and export a reference or self-contained movie out of FCP and bring that into Compressor. Submit the work through your QC. You can then check your system and see all your cores firing away as opposed to just one working on the compressing/encoding/etc. And this really only applies to Quadcore, 8core, etc. Not worth doing it on a duo core.

As of now, it has no effect on tasks such as rendering in FCP or Motion, but there might be other software that's benefiting from it. Probably not though since everything seems to be single threaded still. I don't have much experience with Xgrid to discuss setting it up, but it sounds similar to as if you would link a few machines in Qadministrator. One main machine as a cluster controller and the rest hooked up to to it through ethernet cables as service only machines. Again, this would only be for compressor.

Also, hooking up slower machines to a fast one may be counterproductive.

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