Consequences of using >80% hard memory

Discussion in 'Mac OS X Lion (10.7)' started by Stubaan, Apr 2, 2012.

  1. Stubaan macrumors newbie

    Sep 10, 2008
    Gainesville, FL
    Hey folks

    I have been functioning with about 30-40GB (out of 750) of free memory on my MacBook for the last month or so. I know this is not recommended, and for good reason, but suffice to say it had to be.

    It gets worse; I only rebooted my machine once in that time. This is because the first (and only) time I did so, under such dire memory conditions, the machine wouldn't reboot properly until about the third or fourth attempt. For this reason, among others (concerns about bad fragging) I also ran no updates during this period.

    I am now back to more reasonable circumstances with about 400GB free, fully updated, and am wondering if there are any recommended procedures I should run in an effort to tidy up any consequences from this period.

    I know Mac's do not typically need to be defragged, but I also know they shouldn't be pushed past 80% of their memory. I would love some insight from real fundis about what the consequences of this period may be for my machine's performance, and what you might do in my position.

    Current performance is not terrible, but it is not as slick as it should be for a 2GHz i7 MBP with 8GB ram.

    As always, many thanks!
  2. GGJstudios, Apr 2, 2012
    Last edited: Apr 2, 2012

    GGJstudios macrumors Westmere


    May 16, 2008
    It's fine.
    That's not a problem. Many run for months at a time without restarting.
    If you're talking about hard drive space, it's good to leave at least 10% free (more is better).

    Performance Tips For Mac OS X
  3. simsaladimbamba

    Nov 28, 2010
  4. throAU macrumors 601


    Feb 13, 2012
    Perth, Western Australia
    Whilst everything will work just fine, running with little free space means

    - you are running into the slow part of the disk. the second half (roughly) of the drive is a lot slower than the first half due to lower data density (less data read per revolution of the disk).
    - with less free space available, as you remove and re-add files, there will be less contiguous gaps of free space available, which will potentially increase file fragmentation. fragmented files take longer to read/write as the disk head needs to skip back and forth over different parts of the disk, and this takes time.

    if you CAN free up space, you can potentially get disk access on the machine to be a little faster.

    but - nothing will "break" from running a low amount of free space, unless you actually run out.

    If you want to get your disk back into "optimal" condition after freeing up all that space (all the data at the start of the disk, on the faster part) - you could do a time machine backup and restore, but its a bit of screwing around for probably minimal gain.
  5. benthewraith macrumors 68040


    May 27, 2006
    Miami, FL
    I do recommend you download Onyx. It's a versatile program and you can do a lot of maintenance. Delete old caches, repair disk permissions, verify the disk (which Onyx does by default), and even opens up some parameters that aren't accessible by System Preferences and the Finder.
  6. Mal macrumors 603


    Jan 6, 2002
    The biggest downfall of running with little free space (30-40GB is still ok, though) is that you have less virtual memory available to the system. Since Mac OS X makes use of a significant amount of virtual memory to keep everything running smoothly, it's going to affect performance. Until you get down to ~10GB free, you're usually gonna be ok, but it does depend on what you use your computer for.

  7. Stubaan thread starter macrumors newbie

    Sep 10, 2008
    Gainesville, FL

    I appreciate the input! And peace of mind.

Share This Page