• On BNET: Are these ads too sexy for TV?
advertisement
July 22, 2003 7:40 AM PDT

Tip: Keep some "head room" on your Mac OS X volume for best performance, fewer errors

by CNET staff

A quick reminder that Mac OS X requires at least 10 percent of the volume it is contained on as free space in order to maintain the integrity of the file system. However, even with 10 percent free space, Mac OS X's use swap files - as well as extra data generated by third-party application caches, etc. - can quickly put you back into a position of possible directory/file damage.

Realistically, 20 percent of your Mac OS X startup volume should be kept clear in order to achieve best performance and avoid disk problems.

Choose which files to place on-disk from the Mac OS X Installer's options menu when starting with a fresh installation (or performing an Archive and Install process). You can opt out of unnecessary languages and printer driver support that you will never use, which in some cases can easily make up for the extra 10 percent of head room.

Feedback? Late-breakers@macfixit.com.

Resources

  • Archive and Install
  • Late-breakers@macfixit.com
  • More from Late-Breakers
  • Recent posts from MacFixIt
    iTunes 10 user interface sees some minor changes
    Apple seeds iOS 4.1 Gold Master to developers
    Possible fix for Harman Kardon iSub problems with PowerPC Macs
    Precautions to take before installing iTunes 10
    A reminder on how to reset your Mac's system password
    Mail messages appearing blank
    Adobe Lightroom update brings direct Facebook publishing; Camera Raw 6.2 released
    Weekly troubleshooting utilities update
    Add a Comment (Log in or register) (5 Comments)
    • prev
    • next
    by grikdog July 22, 2003 10:17 AM PDT
    "A quick reminder..." Ha! This is the first time I've heard ANYONE
    mention a disk headroom condition that has been obvious since at least
    10.1.5. Apple has been remiss in explaining this, and in detailing
    whether their VM system can search out and use swap space on ANY
    mounted volume, or just the boot volume. Linux is more transparent
    than Apple's OS X, and Apple is fast running out of good will in some of
    these critical but user-hostile Unix areas.
    Reply to this comment
    by Hildum July 22, 2003 10:17 AM PDT
    <class="merchant"><span>&#62;</span><div class="datestamp"><i>This is a reply to a previous comment by grikdog</i></div></class><br />
    Actually, Micromat has been recommending this for several years now
    on the various forums in Macfixit. Note that they recommend this for
    MacOS 9 as well as OS X. The issue is not Unix in this case.
    Reply to this comment
    by amacaulay July 22, 2003 10:17 AM PDT
    <class="merchant"><span>&#62;&#62;</span><div class="datestamp"><i>This is a reply to a previous comment by Hildum</i></div></class><br />
    I concur. I've been running Macs for 10 years now (since System 7.0)
    and always recommend keeping about 10% of disk space free. I say the
    same to Windows users.
    Reply to this comment
    by thecragus July 22, 2003 2:08 PM PDT
    But why 10%-20%? Does a 120gig HD really need 24gig's left free?
    Shouldn't there be a maximum amount of free space needed regardless
    of the size of the drive? I DO use the 20% rule but have never received a
    satisfactory answer to why so much space is needed on larger drives.
    Reply to this comment
    by Marcvpt July 23, 2003 12:14 AM PDT
    just put your swapfiles on a seperate partition, using for instance
    Xupport. added performance, and you don't have to keep a lot of space
    free on your startup partition. Use a seperate partition of ± 1.5 - 2 Gb,
    and you'll be safe.
    Reply to this comment
    (5 Comments)
    • prev
    • next
    advertisement

    About MacFixIt

    MacFixIt is CNET's troubleshooting resource for all things Mac. The information here helps you navigate the ins-and-outs of Mac ownership with how-tos, troubleshooting information, news, reviews, and more.

    Add this feed to your online news reader