[Beowulf] Reusing cores was Re: Bright Cluster Manager

[Lux, Jim (337K)]

On 5/4/18, 7:36 AM, "Beowulf on behalf of Chris Samuel" <beowulf-bounces at beowulf.org on behalf of chris at csamuel.org> wrote:

    On Thursday, 3 May 2018 11:53:14 PM AEST John Hearns via Beowulf wrote:
    
    > The best successes I have seen on clusters is where the heavy parallel
    > applications get exclusive compute nodes. Cleaner, you get all the memory
    > and storage bandwidth and easy to clean up. Hell, reboot the things after
    > each job. You got an exclusive node.
    
    You are describing the BlueGene/Q philosophy there John. :-)
    
    This idea tends to break when you throw GPUs in to the mix as there 
    (hopefully) you only need a couple of cores on the node to shovel data around 
    and the GPU does the gruntwork.  That means you'll generally have cores left 
    over that could be doing something useful.

>> but compare the "value" of the computational work those otherwise unused cores can do  versus the "cost" of a more complex system management environment.  Isn't the whole idea that "hardware is cheap, wetware is expensive"