Processor Scalability and Linux

[Michael Miles]

JD wrote:
>    On 08/09/2010 01:37 PM, Michael Miles wrote:
>    
>> Kwan Lowe wrote:
>>      
>>> On Sun, Aug 8, 2010 at 1:52 PM, Michael Miles<mmamiga6 at gmail.com>    wrote:
>>>
>>>
>>>        
>>>>>            
>>>> Well, 3D animation is my thing and has been since the Amiga platform.
>>>> The power to render many minutes of animation and still have functional
>>>> machine to do the rest of my daily activity.
>>>>
>>>> I use a virtual machine running windows 7 for my animation software and
>>>> if I want to convert a HD movie at the same time as I do everything else
>>>> it shows a definite slow down.
>>>>
>>>>          
>>> I run a 4-node rendering cluster ( dual quad-cores on each, or 32
>>> cores total and 16G RAM each node).  They're headless and just have
>>> minimal local disks. All nodes write via bonded 2 x 1Gb Ethernet to a
>>> fileserver, but network is usually not the bottleneck. When in use,
>>> CPUs are pegged for hours at a time.  Modeling is done on a quad-core
>>> Windows 7 system with some relatively high-end ATI cards, but gets
>>> final render in the cluster. HD conversion is a minor step since the
>>> renders are done at final resolution.
>>>
>>> My point is that it may be more effective to separate your rendering
>>> hardware. I.e., you can buy a low-end desktop with decent video cards
>>> that will run your software natively *and* a separate, headless
>>> compute node that does all the heavy lifting rather than try to bulk
>>> up a desktop. The desktop will generally have crappy disk i/o, crappy
>>> memory limits (8G is average), crappy network (wireless or GBit), and
>>> your CPU will be busy drawing a pretty desktop than actually rendering
>>> frames.
>>>
>>>        
>> --------------------------------------------------------------------------------------------------------------------------------------------------------------------------
>>
>>
>>
>> I have noticed a bit of a confusing issue.
>> Lightwave running under Win 7 as a virtual machine under Fedora 12 runs
>> faster than a native Win 7 machine.
>> Strange but true.
>>
>> It easily shaves off  2 - 3 minutes / frame as a virtual machine.
>>
>>
>> Anyway thanks for the comments.
>> Question is there a way to have all my cores assigned to one task?
>> I can easily dedicate the cores to a virtual machine but in a native
>> Fedora environment I was wondering if I can get all cores to work on one
>> task.
>>
>>
>> And one other question.
>>
>> What software are you using for your render cluster?
>>
>>
>> Way back in the Amiga days I was using Renderman as a rendering farm and
>> the Screamernet for the Video Toaster.
>>
>> I have been doing some experimentation with Blender and it looks very
>> good but I'm still looking at Lightwave 9 as the best. It is only ported
>> for Windows though making it a pain as I would like very much to use a
>> native linux enviroment.
>>
>>
>> It also seems that Lightwave butterfly netrender for linux is here
>>
>> http://www.weez.com/2010/08/linux-lightwave-render-farm-getting-bnr-butterfly-netrender-to-work-in-debian-possibly-others/
>>
>>
>>
>>
>> We shall see!!!!
>>
>>
>>
>>
>>      
> You can - but indirectly.
> if the process is multithreaded and you want all the cores working on
> those threads, then
> when you start up the process:
> sudo nice -n -10   ProcessPathName
>
> will very likely force all threads get on-core before other threads.
>
> Danger: There are some system processes that MIGHT get preempted by such
> a low priority. Se you need to research to see at what priority (nice
> level) are all the system tasks running.
>
>    

That does work but yes, the system had a bird as soon as I pressed enter
If I wanted to say use 3 out of 4 on a single process and use the 4th 
free core for the system how would I go about that?

Thank you by the way!!!


Michael