CPU usage and hyperthreading


    Feb 02 2012 | 11:11 pm
    Hi,
    I've recently built a granular synth/sampler using a groove~ inside a poly~ and have noticed that the max audio status says that I'm using around 20% CPU when its running at full tilt with 16 instances. The CPU monitor in OSX however says that max is using between 70% and 115% CPU. I'm slightly worried as to the discrepancy between the two, not to mention the fact that apparently my CPU can work at 115%. I have tried using two poly~'s in tandem, each running 8 instances with the parallel setting switched on to see if this eases the processor load but to no avail. I was wondering if anyone has any advice re: the discrepancy in CPU readout or how I might achieve some effective parallel processing.
    Thanks in advance
    Benny

    • Feb 03 2012 | 12:12 am
      Is parallel on in the first instance?
      A few things to note:
      1 - Audio status only looks at the CPU used to cacluate audio. :You may be seeing graphical stuff or something else.
      2 - For Max 100% means "no CPU time left", so that means all processors/cores maxed out. Activity monitor shows 100% for one core maxed out, so if you are running acoss 4 cores at 80% in activity monitor, you would expect to see about 20% in the max CPU monitor.
      It sounds to me like everything is fine - the figures just mean something different to what you expect.
      Alex
    • Feb 03 2012 | 8:26 am
      Hey Alex,
      Thanks for your response. I have parallel turned on in the inspector and in DSP setup (Max6). I have also tred tried sending parallel messages to the poly~ objects etc...
      I was hoping to see some sort of vast drop in CPU usage with the parallel processing switched on but from your explanation I can sort of understand why not. Also I read recently that having a dual core processor won't actually double your processing power rather than add around 25%. I'm not sure how true this is myself?
      Benny
    • Feb 05 2012 | 11:32 am
      I just bought Gen and now all the above is being far less CPU intensive!? Bearing in mind that I haven't altered anything to include any Gen patches, does Gen somehow unlock some different processing capabilities for the overall MSP engine or is this a Max quirk?