2011 MBP - Useful to have 2 partitions?

Discussion in 'MacBook Pro' started by ApplePu, May 5, 2011.

  1. ApplePu macrumors regular

    Apr 3, 2010
    I've read somewhere that one can get a better performance if he is working on 2 partitions, so for example on a 750GB Scorpio Black:

    Partition 1: 150 GB for system + applications

    Partition 2: 600 GB for storage

    The reason for the performance increase is that partition 1, so system and applications, would be only using the faster outer rim of the mechanical disk.

    Can anybody confirm the advantages of this procedure or is the whole thing just a myth? I can't find really reliable information about this.....
  2. ZombieZakk macrumors 6502

    Feb 23, 2011
    i cannot see this being noticeably different if you could guarantee it would use a denser platter then it might but i have a hard time believing this to be noticeably beneficial.
  3. discounteggroll macrumors 6502


    Aug 6, 2006
    Greenwich, CT
    I doubt you'd notice any real difference in performance. If you want known working performance gains, I would go with a SSD in your main HD bay for the OS and throw that 750GB Scorpio Black in the optical drive bay for your home directory/storage.
  4. maflynn Moderator


    Staff Member

    May 3, 2009
    You won't see any performance boost because you divided up the same HD. The data is going through the same controller and so you'll not notice any boost. Only with two drives going through two controllers will you see the boost.
  5. mape2k macrumors regular

    Apr 18, 2011
    However, there is the advantage of separated fragmentation of the two partitions. If you move a lot of files onto and off the storage partition and it gets fragmented, it will not reduce the performance of the system partition.
  6. ApplePu thread starter macrumors regular

    Apr 3, 2010
    So overall:

    There is no real gain in performance, but there aren't any disadvantages to do it.....do I get it right?
  7. cambookpro macrumors 603


    Feb 3, 2010
    United Kingdom
    So why would you do it if a) it takes time and b) has no advantages?
  8. ApplePu thread starter macrumors regular

    Apr 3, 2010
    Because this guy is convincing me somehow:


    All his explanations and especially the "Two Partitions" part seem quite logic to me. But I don't have detailed enough technical knowledge to judge if this guy knew what he was talking about.

    That's the reason I'm asking the community....to get enlightened :)
  9. jegbook macrumors regular

    Dec 2, 2007
    The only time I could really see the multiple partition setup helping out is with applications that use a decent chunk of space as a scratch disk (Photoshop for instance). Having one partition that would have a fair bit of free space that wouldn't get fragmented so the scratch disk space could be contiguous.
    That said, it would only be helpful if the application allows you to specify a partition to use as the scratch disk. And if you could, I would actually think the thing to do woud be do to partition your drive to have one primary large partition and one small partition at 10 - 15 GB. Then never put any data on this partition and specify it as the scratch disk for any applications that allow you to.

    Otherwise, it seems a waste of time. I can't see how the stratgey would offer any noticeable speed differences. And since OS X puts your personal data on the boot volume in your user directory, the strategy complicates data management.

    I didn't read the link, but is there an argument that when you partition a drive you know where each partition on a drive is physically? How do we know how to trust the software to reliably partition a drive phsyically?
    Sounds funky.
  10. jerry333 macrumors regular


    Nov 4, 2005
    Multiple partitions are from the days when drives were small and much less reliable. The idea was that if you had multiple partitions:

    1. Logfiles, mail spool, etc. wouldn't fill up the system drive and halt the computer.

    2. When the drive failed, if you had multiple partitions, it might not be the booting partition that had the failure so you had a reasonable chance of getting most of your data off. If you made the bootable partition very small, you reduced the chance of failure in the boot partition even more.

    Today with big and reliable hard drives, these reasons don't make a lot of sense.

    As far as fragmentation goes, it's not really a problem on a Unix filesystem because every new file is guaranteed to be written to a contiguous space. Rewrites might get fragmented, though but it takes quite a while for that to happen enough to affect performance.

    There is a good reason for two drives. One for /Users and one for /Macintosh HD. This allows reads and writes to happen at the same time in both user space and system space. In addition, upgrades and re-installs are safer because your data is on a separate disk.

Share This Page