Slashdot Mirror

← Back to Stories (view on slashdot.org)

Quick, Standard Measurement for CPU Power?

Posted by Cliff on from the you-can-keep-your-bogomips dept.

captnitro asks: "A particular research project I'm developing right now needs to compare 'potential' (idle/none) and 'load' for various hardware capabilities, and quickly -- maybe up to a several times every minute. For disk space, for RAM, it's relatively easy -- find what's used and what's not and report the ratio. For CPU, I have plenty of time to test 'potential' when the app starts. But for testing CPU load, I need a standard 'ruler' that will be able to compare across varying platforms and processors (e.g., x86, PowerPC, embedded, single and multi-proc) -- so for example, idle percentage won't work. At the same time, I don't have the ability to time 'openssl speed' every 25 seconds without bringing the system to a halt. I'm willing to sacrifice precision of the measurement for generalization of the unit -- that is, the operations that this test is for would be primarily mathematical and not say, text sorts -- but I'd prefer a generic, quick test of the current processor load rather than an average of 25 different tests. Regardless of hardware, the OS distribution is mostly *nix-based -- NetBSD, Linux, and even Mac OS X. Wild ideas are perfectly acceptable -- any thoughts?"

2 of 31 comments (clear)

  1. Re:go ahead and use idle percentages by MerlynEmrys67 · · Score: 2, Interesting
    As mentioned above - for a general purpose OS - you have to take priority into account. I can keep a machine at 100% CPU utilization - and it will have 99+% available to anyone that comes along with a higher priority.

    What are those priorities, Interupt handling, high priority applications, ???

    What this person might be considering is some kind of batch job scheduling environment - where you want to schedule an incoming job on the system with the greatest current capacity to process it. ie. using free resources around the network to do useful work.

    --
    I have mod points and I am not afraid to use them
  2. Random idea.. by Anonymous Coward · · Score: 1, Interesting

    1) do some research on figuring out the relationship between Amps (current draw) and units of computation per time (like flops maybe). I.e., is it a linear relationship? Come up with a relationship.

    2) Using #1, calculate the current draw of CPU (perhaps use a separate dedicated power supply for the CPU and/or mobo) and therefore the current CPU utilization.

    You might need to address temperature in there too. Or *only* use temperature rather than current (for instance temperature difference between the outside of the case and the CPU).

    Just an idea. Some CPUs are more efficient than others so you have to scale it, but doesn't it make sense that CPU power is proportional to real power?