How much free space should you have on your system drive for optimum performance?

Discussion in 'iMac' started by discofuel, May 11, 2011.

  1. macrumors 6502

    Feb 21, 2010
    My 1TB hd in my iMac has 2gb free and now can't even play songs on iTunes without major glitching and stuttering.

    I've ordered a 2TB external to take care of that and will just use my internal for system.

    When does lack of free space start degrading performance and how much free space is it recommended to have?
  2. simsaladimbamba

    Nov 28, 2010
    It is recommended to have 10 to 20 percent of the HDD's capacity unused, for temporary files.
    But with such large HDDs, 100GB should more than suffice, but 2GB free HDD space is really not good. It can even lead to hardware failure.
  3. macrumors 6502

    May 6, 2011
    That's A LOT of stuff! Sounds like you should be putting some of your less used stuff on an external. Other than that you could try deleting some of the crap (we all have it)
  4. macrumors regular

    Sep 7, 2010
    At this stage, having filled the disk up so much, you probably have many fragmented files. These are files which are recorded in discontiguous pieces on the disk. This slows things down.

    File fragmentation means a more complex directory or index, which also slows things down.

    I would recommend moving enough files off this disk to reduce the space utilization to below 80%. Lower if you plan to add stuff later. Then copy the remaining files somewhere else, erase this 1TB disk, and copy the files back. This will result in a defragmented disk that should perform well.

    For even more performance, buy a 3TB disk, and copy all the files to that. The files will be much closer to each other on the larger capacity disk and take less time to access. As the disk fills up, access time will again increase.
  5. thread starter macrumors 6502

    Feb 21, 2010
    My new 2TB FW800 drive is arriving on Friday.

    In the meantime I've deleted 30GB off the internal drive but the system is now so slow it's now barely responsive...

    Rainbow wheel of death when opening up folders and takes ages to even show folder contents.

    Whole computer freezes even when scrolling down the page on Safari.

    Had a look at the disk activity and I'm getting huge read spikes all the time.

    I did a full defrag with idefrag a couple of weeks ago. Could there be a problem with the internal drive or corrupted OS?
  6. macrumors 6502a


    Apr 1, 2011
    When the Externel Harddrive arrives, i'd throw all the crap you need on to that, and do a clean reinstall of the entire system..
  7. thread starter macrumors 6502

    Feb 21, 2010
    Yup, that's a good idea. Although not looking forward to the hours it will take to install and authorize my hundreds of audio plugins :eek:

    Is it recommended to leave my user folder on the internal and just move my project folders to the external or move the entire home directory?
  8. macrumors newbie

    Jun 1, 2008
    Try this. go to disk utilities and do a repair disk. This might fix the problem you are having.
  9. macrumors 6502

    Nov 20, 2009
    Calgary, Canada
    Hi discofuel,
    don't use that computer too much 'till you can clean it up some more.
    This is a shot of my Mac using over 170Gb for VM (virtual memory).
    This has to be provided by the HD, since you don't have that much RAM, do you?
    If it's not available the Mac can lock-up & you'll have a hard time to fix it...:

    Attached Files:

  10. simsaladimbamba

    Nov 28, 2010
    So you registered three years ago and the only post you make is a reply to a five months old thread, which you revive with your only post?

    That is not true.

    As you can see from the above screenshot, I am having 176GB virtual memory. But nowhere on my 60GB SSD can this be found or even stored.
    Btw, it is GigaByte (GB), not Gigabit (Gb), as 1B = 8b.

  11. macrumors newbie

    Oct 22, 2011
    I use an app called daisy disk from the app store, pretty handy and very good looking lol
  12. thread starter macrumors 6502

    Feb 21, 2010
    Wow, wasn't expecting this thread to reopen!

    In the end I installed a 120GB SSD just for my OS and a 2TB internal for all my data.

    My iMac is now superfast and free of all problems :)

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