64bit Apps on Leopard

Discussion in 'macOS' started by pacmania1982, Feb 18, 2009.

  1. pacmania1982 macrumors 6502a

    pacmania1982

    Joined:
    Nov 19, 2006
    Location:
    Birmingham, UK
    #1
    OK - so I just opened up Activity Monitor to force quit an app, and to my surprise I have two processes that are running as 64bit... I thought this was a Snow Leopard thing??

    Anyone else seen this?

    pac
     

    Attached Files:

  2. yippy macrumors 68020

    yippy

    Joined:
    Mar 14, 2004
    Location:
    Chicago, IL
    #2
    Leopard and even Tiger have been able to run 64bit apps. The buzz about Snow Leopard is that it will be fully 64bit instead of mixing 64bit and 32bit code in the OS itself.
     
  3. sidewinder macrumors 68020

    sidewinder

    Joined:
    Dec 10, 2008
    Location:
    Northern California
  4. armoguy94 macrumors 6502

    Joined:
    Nov 9, 2007
    #4
    None of my processes running right now are 64 bit under leopard :(
     
  5. mongrol macrumors regular

    Joined:
    Jul 16, 2007
    #5
    Really, people need to get away from the 64bit obsession. The performance difference between 32bit and 64bit is usually negligible. The main advantage of 64bit is that it allows applications to use massive amounts of memory.
     
  6. ElectricSheep macrumors 6502

    ElectricSheep

    Joined:
    Feb 18, 2004
    Location:
    Wilmington, DE
    #6
    Aside from a larger addressable virtual and physical address space, x86-64 also brings the to table:

    • 64 bit wide registers with support for 64 bit integer operations.
    • 16 general purpose registers, as opposed to x86's eight. Function calls can pass more parameters via GP registers as opposed to having to pull them from L1 cache.
    • The ability to reference data relative to the Instruction Pointer, which can improve the performance of shared libs and dynamically loaded code.
    • An XD bit, which can defeat certain types of buffer overflow exploits.

    I suppose, depending on your code, if you refactor and/or aggressively optimize for x86-64, you might be able to get as much as a 10 to 15 percent performance boost. By no means is it a sure thing, but there is more to moving to 64 bits than address space.
     
  7. Tallest Skil macrumors P6

    Tallest Skil

    Joined:
    Aug 13, 2006
    Location:
    1 Geostationary Tower Plaza
    #7
    PANTHER even had built-in 64-bit support.

    Jaguar had support to run on 64-bit processors.
     
  8. Catfish_Man macrumors 68030

    Catfish_Man

    Joined:
    Sep 13, 2001
    Location:
    Portland, OR
    #8
    No it didn't. 64 bit processes were new in Tiger, 64 bit GUI applications are new in Leopard.
     
  9. Tallest Skil macrumors P6

    Tallest Skil

    Joined:
    Aug 13, 2006
    Location:
    1 Geostationary Tower Plaza
    #9
    It wasn't full support, but it was there.
     
  10. Amdahl macrumors 65816

    Joined:
    Jul 28, 2004
    #10
    That is true on PowerPC, but Intel/x86 architecture is crap with only 8 addressable registers. AMD64 expands the number of registers to 16.

    It really is amazing that Rosetta was able to get PPC code (which has 32 registers) to work so well on the puny 8 register Intel chips.

    Isn't the XD bit the same as the AMD NX-bit, which has been around since at least 2003?
     
  11. Catfish_Man macrumors 68030

    Catfish_Man

    Joined:
    Sep 13, 2001
    Location:
    Portland, OR
    #11
    Even on Leopard the kernel is limited to 4 gigs of address space. I suppose it had the minimum changes necessary to map that address space anywhere in a larger physical memory.
     
  12. pacmania1982 thread starter macrumors 6502a

    pacmania1982

    Joined:
    Nov 19, 2006
    Location:
    Birmingham, UK
    #12
    Actually, if you read what I put, I wasn't obsessed with the difference between 32bit and 64bit. I was simply asking if this was normal as I hadn't seen it before

    Chill out!

    pac
     

Share This Page