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startup disk space

2412 Views 5 Replies Latest reply: Jan 27, 2010 9:27 AM by cornelius RSS
jseerden Calculating status...
Currently Being Moderated
Jan 26, 2010 1:04 PM
I have used disk utilities to copy and burn dvds (not copywritten) several times. Now when I try to create a new disk image file I get a window that says "Your startup disk is almost full. You need to make more space available on your startup disk by deleting files". I have deleted everything else that I had as an image file, plus pictures, ran MacJanitor and am still getting that window. What am I doing wrong? Thanks
Mac OS X (10.4.11)
  • BDAqua Level 10 Level 10 (114,825 points)
    Currently Being Moderated
    Jan 26, 2010 1:16 PM (in response to jseerden)
    Hi there,

    Are you using FileVault by any chance?

    How much free space is on the HD, where has all the space gone?

    OmniDiskSweeper is likely the easiest/best, and is now free...
  • BDAqua Level 10 Level 10 (114,825 points)
    Currently Being Moderated
    Jan 26, 2010 2:45 PM (in response to jseerden)
    Oh no, 1.3 GB is even dangerously low for OSX, it may decide it needs 10GB for VM space at any time, I have 6 GB of Free real RAM & my VM is at 26GB of Disk space now.

    See if you can't get at least 20 GB free space.
  • Texas Mac Man Level 8 Level 8 (44,340 points)
    Currently Being Moderated
    Jan 26, 2010 3:25 PM (in response to jseerden)
    What size HD do you have & how much RAM?

    Your Mac needs adequate hard drive space to operate normally. How full can a drive be before it's too full? There is no hard and fast rule that says “X” amount or “%” of free drive space is needed. A low amount of RAM requires more drive space for Virtual Memory’s swap files. As a general rule, your available space should be 5GB as an absolute minimum as it generally requires that much free space to perform an Archive and Install of Mac OS X and still preserve some free space for VM swap files.

    Problems from insufficient RAM and free hard disk space are discussed in this link

    Look at these links.

    Where did my disk space go?
    Download & use WhatSize described in this link or Disk Inventory X @

    Freeing space on your Mac OS X startup disk

    Amazing Disappearing Drive Space

    Increase HD Free Space top.html

    How to free up my disk space

    Where Did My Disk Space Go? 1

     Cheers, Tom

     G4 1.25MHz MDD, G3 400 FW Pismo,, Mac OS X (10.5.6), OS 10.4.11/9.2.2, Canon LiDE30 Scanner, Canon i960 Printer, Belkin UPS
  • cornelius Level 6 Level 6 (17,825 points)
    Currently Being Moderated
    Jan 27, 2010 9:27 AM (in response to jseerden)

    Here is the not "hard and fast" rule. If your computer's HDD is 40 GB or less you need to maintain a minimum of 5 GB as contiguous (unfragmented) free space. HDDs over 40 GB need a minimum of 15% of total disk capacity as contiguous free space. Yes, part of the function of free space is for swap files. More critical, however, is maintaining free space to allow the Extent Overflow File in the directory to lay down new pieces of the file as that data on the drive increases. Without that much contiguous free space you can end up with directory corruption as the Extents Overflow File begins overwriting extents that already have data on it. You then end up with overlapping volume structures which can only be corrected by removing data from overlapping extents so that there is only one piece of data on those extents. The pieces of data that are removed are deleted, so your data files may become irretrievably damaged.

    I suggest that you maintain 20% of total capacity as free space to be sure there is enough contiguous free space. In your case, sounds like your computing habits dictate a larger capacity HDD. I suggest that you make a full backup/clone of your HDD immediately and install a larger capacity HDD.

    MBP 2.4 GHz 6 GB RAM, 200 GB HDD; VMwFusion: XP Pro, Ubuntu, Mac OS X (10.6.2), PismoG4/550, 120GB 5400 HDD (10.4.11); Beige G3 OS 8.6


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