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Defragmenting a fragmented system disk on Windows 8 RRS feed

  • Question

  • I just upgraded from Windows 7 to Windows 8 and also upgraded to Office 2013,  In connection with the upgrades, I imported emails, cleaned up old documents, organized files and deleted old programs.  After finishing this, I looked at the status of my disks and found that the system hard drive is more than 55% defragmented and needs optimization.  I pushed the "optimize" button, it works for a couple of seconds and comes back saying I'm still over 55% defragmented and updating the time of the last defragment to the current time.  I reset the automatic defragment process to occur every day, pushed the button and left the computer on for the night.  The next morning, I get the same message.  It doesn't look like anything happened.  Is something wrong with the disk, should I run the function from the command line or what.  I understand that the defragment function is passive and takes a long time but I expected I would get a status bar that would show progress on the defragmentation process.  That doesn't happen.  It looks like the defrag function simply isn't working on Windows 8.  Do you have any suggestions.  Also, I tried to post this to the Windows 8 forum but it pushed me to Windows 7 instead.  Not sure why that happened.  Thanks for your help.   
    Sunday, August 11, 2013 1:47 PM

Answers

  • Windows skips files which are over 64MB:

    Not so in Windows Vista if the fragments are large enough – the defragmentation algorithm was changed (from Windows XP) to ignore pieces of a file that are larger than 64MB. As a result, defrag in XP and defrag in Vista will report different amounts of fragmentation on a volume. So, which one is correct? Well, before the question can be answered we must understand why defrag in Vista was changed. In Vista, we analyzed the impact of defragmentation and determined that the most significant performance gains from defrag are when pieces of files are combined into sufficiently large chunks such that the impact of disk-seek latency is not significant relative to the latency associated with sequentially reading the file. This means that there is a point after which combining fragmented pieces of files has no discernible benefit. In fact, there are actually negative consequences of doing so. For example, for defrag to combine fragments that are 64MB or larger requires significant amounts of disk I/O, which is against the principle of minimizing I/O that we discussed earlier (since it decreases total available disk bandwidth for user initiated I/O), and puts more pressure on the system to find large, contiguous blocks of free space. Here is a scenario where a certainly amount of fragmentation of data is just fine – doing nothing to decrease this fragmentation turns out to be the right answer!

    http://blogs.msdn.com/b/e7/archive/2009/01/25/disk-defragmentation-background-and-engineering-the-windows-7-improvements.aspx


    "A programmer is just a tool which converts caffeine into code"

    • Marked as answer by tracycai Tuesday, August 13, 2013 6:17 AM
    Sunday, August 11, 2013 6:17 PM

All replies

  • Consider investing in a very robust utility, such as PerfectDisk.

    Carey Frisch

    Sunday, August 11, 2013 4:38 PM
  • How much free disk space have you got on the drive? If there isn't enough space to move data around the defrag program can't generally do as good a job.

    Would definitely agree with Carey though about using a different defrag app. There are plenty of others out there, free and paid for, which tend to do a better job (and give more options) that the built in on. Personally I tend to use free version of Auslogics Disk Defrag.

    Sunday, August 11, 2013 5:15 PM
  • Windows skips files which are over 64MB:

    Not so in Windows Vista if the fragments are large enough – the defragmentation algorithm was changed (from Windows XP) to ignore pieces of a file that are larger than 64MB. As a result, defrag in XP and defrag in Vista will report different amounts of fragmentation on a volume. So, which one is correct? Well, before the question can be answered we must understand why defrag in Vista was changed. In Vista, we analyzed the impact of defragmentation and determined that the most significant performance gains from defrag are when pieces of files are combined into sufficiently large chunks such that the impact of disk-seek latency is not significant relative to the latency associated with sequentially reading the file. This means that there is a point after which combining fragmented pieces of files has no discernible benefit. In fact, there are actually negative consequences of doing so. For example, for defrag to combine fragments that are 64MB or larger requires significant amounts of disk I/O, which is against the principle of minimizing I/O that we discussed earlier (since it decreases total available disk bandwidth for user initiated I/O), and puts more pressure on the system to find large, contiguous blocks of free space. Here is a scenario where a certainly amount of fragmentation of data is just fine – doing nothing to decrease this fragmentation turns out to be the right answer!

    http://blogs.msdn.com/b/e7/archive/2009/01/25/disk-defragmentation-background-and-engineering-the-windows-7-improvements.aspx


    "A programmer is just a tool which converts caffeine into code"

    • Marked as answer by tracycai Tuesday, August 13, 2013 6:17 AM
    Sunday, August 11, 2013 6:17 PM