Results 1 to 8 of 8

Thread: why does my system think I have a dual-core?

  1. #1
    Join Date
    Feb 2008
    Location
    TX
    Beans
    316
    Distro
    Hardy Heron (Ubuntu Development)

    why does my system think I have a dual-core?

    I have an Acer Aspire One netbook. With intel Atom. Gnome's System Monitor, top, htop, and kpowersave all think I have two CPUs. Htop's CPU usage meters even individually move back and forth.

    Hello? Did I get a preproduction dual-core Atom?

  2. #2
    Join Date
    Sep 2007
    Location
    England
    Beans
    1,103

    Re: why does my system think I have a dual-core?

    Hyper-threading
    http://en.wikipedia.org/wiki/Hyper-threading

    Physically it's a single core CPU
    but the OS "sees" a dual core because of the CPU hyper-threading

  3. #3
    Join Date
    Nov 2007
    Location
    Kuwait
    Beans
    286

    Re: why does my system think I have a dual-core?

    I have an Aspire one as well, I have windows installed and it also shows 2 processors.

  4. #4
    Join Date
    Feb 2008
    Location
    TX
    Beans
    316
    Distro
    Hardy Heron (Ubuntu Development)

    Re: why does my system think I have a dual-core?

    So if I had a quad-core, would ubuntu see all four cores or would it also say I had a dual-core?

    My friend has kubuntu 8.04 and he says his system only shows one CPU.

  5. #5
    Join Date
    Jan 2006
    Beans
    192
    Distro
    Ubuntu 8.04 Hardy Heron

    Re: why does my system think I have a dual-core?

    Quote Originally Posted by BetterSense View Post
    So if I had a quad-core, would ubuntu see all four cores or would it also say I had a dual-core?

    My friend has kubuntu 8.04 and he says his system only shows one CPU.
    4cores

  6. #6
    Join Date
    Sep 2007
    Location
    England
    Beans
    1,103

    Re: why does my system think I have a dual-core?

    If you had a quad-core hyperthreaded Intel CPU (which don't exist as far as I'm aware, but just pretend) the OS would see eight cores

    hyperthreading is hardware-based multi tasking implemented on certain intel CPU's (as opposed to the software scheduling done in the kernel)

    physically, there's X cores
    logically, there's 2X cores

    if your friend has a single core, and the OS "sees" it as a single core, then it's not got hyperthreading

  7. #7
    Join Date
    Jun 2006
    Location
    The Netherlands
    Beans
    2,185
    Distro
    Ubuntu 12.04 Precise Pangolin

    Re: why does my system think I have a dual-core?

    Quote Originally Posted by amauk View Post
    If you had a quad-core hyperthreaded Intel CPU (which don't exist as far as I'm aware, but just pretend) the OS would see eight cores
    It does exist - the brand new Intel Core i7 processors have four cores and hyperthreading, so it will look like there are eight cores to the OS.
    Ubuntu 12.04

  8. #8
    Join Date
    Nov 2007
    Location
    Kuwait
    Beans
    286

    Re: why does my system think I have a dual-core?

    for the curious ones
    Attached Images Attached Images

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •