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Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

Any way to use hyper-threading?

I'm running Quartus II 9.0 SP2 on a quad-core Intel Core i7 920. This is the latest line of Intel chip, which features the return of hyperthreading, so there's actually 8 processors total. However, Quartus doesn't want to use more than 4. I've set it to "Use all available processors" in Settings -> Compilation Process Settings, but it says it only detects 4. It won't let me explicitly select more than 4 either. I even tried manually editing the .qsf file to set NUM_PARALLEL_PROCESSORS to 8, but the messages printed during compilation still say that it's only using 4.

What I'm wondering is, is this a bug in Quartus where it doesn't correctly detect the presence of the hyperthreaded processors, or is it a deliberate restriction made by the Quartus developers after evaluating the benefits and drawbacks of hyperthreading on the new Core i7 line?

P.S. I'm using Ubuntu, in case it matters.

P.P.S. The OS does recognize all 8 processors.

2 Replies

  • ocraM's avatar
    ocraM
    Icon for New Contributor rankNew Contributor
    2 years ago

    I know this is old but has there been any update on this?
    The link http://www.altera.com/support/kdb/solutions/rd03222007_376.html from the last comment is leading me to altera home page.

    I'm having the same problem on an 4-core 8 threads processor machine with Quartus 23.1 lite. I tried adding

    set_global_assignment -name NUM_PARALLEL_PROCESSORS 7


    to my qsf file but i get

    Warning (20031): Parallel compilation is enabled for 7 processors, but there are only 4 processors in the system. Runtime may increase due to over usage of the processor space.