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  1. Old Comment

    Un-met Expectations -- a real example

    Quote:
    There is another skid mark on this topic. That is the issue of 32-bit vs. 64-bit vs. physical memory. As I understand things, 4 Gbytes of ram is 2**32 bytes. In contrast a 32-bit address space can access 2**32-1 bytes -- one less -- physical bytes. Therefore, a 32-bit distro release requires the physical address extension (PAE) kernel package to access all of the 4 Gbytes of physical ram. This applies not only to the running kernel but also
    to the boot loader. A 64-bit distro release does not have these limits. Your mileage may vary.
    Not exactly. 4 Gbytes of ram is 2**32 bytes and a 32-bit address space can access exactly 2**32 bytes (0 through 2**32-1 bytes inclusive). BUT, the motherboard BIOS will want some of that 32-bit address space (typically the last gigabyte) for its hardware, leaving only 3 Gbytes or so for actual addressable ram in the 32-bit address space. Any ram beyond that amount, the motherboard will bump up beyond the 32-bit address space. Therefore, if you have 4 Gbytes of physical ram, you will need to use PAE in the kernel in order to be able to see all 4 Gbytes of ram. Otherwise, you will only see the 3 Gbytes or so that the motherboard allows in the 32-bit address space. PAE is clever hand waving in the microprocessor paging module that essentially allows the microprocessor to generate a 36-bit address (64 Gbytes addressable) from the 32-bit address it is given. A 64-bit distro release does not have these limits, since it uses long mode in the microprocessor chip and that uses a 64-bit address space (17179869184 Gbytes addressable).
    Posted 08-04-2014 at 03:08 AM by xode xode is offline
  2. Old Comment
    Posted 10-11-2012 at 03:49 AM by brianL brianL is offline
  3. Old Comment

    My Choice of Avatar -- The Sorcerer's Apprentice

    hey there saint i too have a thinkpad tablet trying to convert to linux any help would be an absolute godsend as i have no transport untill i finish conversion as tablet will be running the auto tune function in my car to make it run and as a media player for my sounds yours sincerely loopsta!
    Posted 10-09-2012 at 09:57 PM by loopsta loopsta is offline
  4. Old Comment

    My Choice of Avatar -- The Sorcerer's Apprentice

    By the way, I failed to give due credit. The Sorcerer's Apprentice was a Disney character in the original Fantasia film (1940). The experience was so special that it was repeated in Disney's the second Fantasia (2000) film.
    http://www.google.com/url?sa=t&sourc...fPpQA46jputLhg

    The character, Sorcerer's Apprentice, was made into its own feature film http://www.google.com/url?sa=t&sourc...i4D7BNqSyN1z9w released in 2010.

    All rights belong to the respective trademark and copyright holders. I'm a fan along for the ride.

    ~~~ 0;-Dan
    Posted 09-29-2010 at 10:57 AM by SaintDanBert SaintDanBert is offline

  



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