64 bit verus 32 bit os

Discussion in 'General Electronics Chat' started by vustudent, Aug 15, 2010.

  1. vustudent

    Thread Starter Active Member

    Mar 11, 2009
    Since a 64 bit operation system runs with more bits to a processor, would it be inefficient and possibly slower in performing certain trivial tasks than the 32 bit os?

    For example, if you are performing addition of two numbers:
    A = decimal 1
    B = decimal 3

    where under a 32 bit os A would be 31 zeros and a one, and B 30 zeros and two ones. While under a 64 bit os, there would be more zeros passed to the processor describing the same number and then performing the addition.
  2. Potato Pudding

    Well-Known Member

    Jun 11, 2010
    More parallel bits will generally be faster and no slower.

    Look at the bitwidth as 64 logic streams with a carry.

    Each logic stream is as fast as it is and doesn't worry about how many logic streams are in parallel.
  3. kingdano

    Senior Member

    Apr 14, 2010
  4. marshallf3

    Well-Known Member

    Jul 26, 2010
    Actually makes no difference with simple things, it's when you get into the more complicated programs that the CAPABILITY of being able to handle a 64 bit wide bus comes into play.

    For ages the command set of the actual thinking part of a CPU was only 8 bits wide anyway and may still be for all I know.
  5. kingdano

    Senior Member

    Apr 14, 2010
    its definitely on the programmers to utilize the 64-bit architecture and take advantage of the extra processing gusto.

    if you run a 32-bit program on a 64-bit OS you gain little (if any) performance.

    but true 64 pit programs do run much more quickly than the same program written in 32-bit.

    LabVIEW for example - the 64 bit version runs more smoothly in me experience.
  6. tom66

    Senior Member

    May 9, 2009
    The ability to move 64 bits at a time is an advantage. For example, the 32 bit version of glib's strcpy copies up to 4 bytes at a time, while the 64 bit version copies up to 8 bytes a time: 2x speed increase.
  7. marshallf3

    Well-Known Member

    Jul 26, 2010
    I've found little that can take advantage of 64-bit although the gamers have, I've also found a lot of things that run on 32 but won't run on 64 without "cheating" so to speak.

    Out of all the PCs on my home network only one runs XP Pro 64, it's a file server and you need a 64 bit OS in order to take advantage of GPT/GUID partitioning so you can break the 2 TB limit on hard drive RAID sets.
  8. studiot

    AAC Fanatic!

    Nov 9, 2007
    This is an oversimplification, stemming from a fundamental misconception.

    The efficiency, or otherwise, of a processor, depends largely upon the match of the 'real' data width being processed with the address width.
    Don't forget that much processor work is taken with calculating and processing addresses.

    A processor with a 64 bit address space and 64 bit data space is no more or less efficient than one with a 4 bit address space and 4 bit data space.
  9. nsaspook

    AAC Fanatic!

    Aug 27, 2009
    In a threaded and/or multitasking OS even with less than 32 bits of memory the ability to use 64 bit atomic operations for locks or synchronization can make context switches/OS system calls faster by packing structures into a 64 bit register. The ability to crunch twice the data in the same clock cycles is pretty cool also when using written for 64 bit tools.

    kingdano likes this.