What is “defragging” and why should I do it?

Defragging rearranges the layout of files on your hard disk for faster access. Specifically when (or even if) you need to do it at all is evolving.

“Defragging” is short for “de-fragmenting” and it’s a process run on most hard drives to help make accessing the files on that disk faster.

Traditionally, it’s something you need to do periodically as files on the disk become more and more fragmented over time (hence, the term “defragmenting”).

So, what does it mean to be fragmented? Why does it get worse over time?

I’ll review that, as well as how to defragment, when to defragment, and even if you need to worry about defragmenting at all.

Fragmentation

To you and me, a file on your disk is a single thing. You open it, you work on it, you save it. It’s a single entity. We might compare it to say a book.

To your computer, however, a file is a lot more like a bunch of pages in that book that it has to keep track of individually.

Imagine that you have a book, but that the pages are randomly scattered throughout your house. You have a list of where each page is, so when you want to read your book you go find page 1, then you look on the list for page 2 and go to that, then look up page 3, and so on. In order to read your book in order, you’re racing around the house like crazy because the pages are all over.

That’s a fragmented file. The sectors1 that make up the file are scattered all over the disk. The result is that when you access the file, Windows has to race all over the
disk to retrieve the whole thing. That takes time.

Defragmentation

Defragmentation is nothing more than pulling all the pages/sectors together in order, so that they’re close to each other. In an ideally defragmented disk, the sectors of each file would be in an orderly sequence one right after the other, just like the pages in a book.

An Active Hard DIskNow, UNlike the pages of a book strewn about your home, disk sectors are a little more limited in how they can be laid out. The result is that in order for the sectors of one file to be able to be arranged in a defragmented order, other files or fragments of files may have to be first moved out of the way to make room.

In fact, that’s what a defragmenting tool spends most of its time doing: moving files around on the disk to make room so that other files can be laid out in order.

It’s also one of the things that differentiates one disk defragmenting tool from another: some are simply better or more efficient at moving things around as little as possible so as to be done as quickly as possible with an result that’s as acceptable as possible.

Why fragmentation happens

Fragmentation happens because files on the disk are constantly changing; being created, deleted, grown, or shrunk in size. And all of that happens in a fairly random order.

For example purposes, let’s say we have a very tiny disk that has exactly 12 sectors and no more.

On this disk, we’ve created three files: file1, file2 and file3:
Three files on a tiny disk
File 1 takes up two sectors, file 2 takes two, and file 3 takes up five sectors on the disk, leaving three sectors free at the end.

We now delete file 2:
Deleting a file on a tiny disk
As you can see, that leaves a “hole” of two empty sectors between the remaining files 1 and 3.

Now, we’ll create a new file, file 4, which is four sectors long:
Adding a file to a tiny disk
The only way to store file 4 is to split it into two fragments: two sectors in part “(a)” and two sectors in part “(b)”.

It’s important to note that this all works just fine. The fact that files are fragmented is handled quite transparently by the operating system and the file system. The various pieces of the files are all kept track of and located as needed.

It’s just that in our silly little example above if we want to read file 4 from end-to-end, we need to spend a little time “skipping over” file 3. If file 4 were in one contiguous set of sectors, it’d be a tiny bit faster.

Making that happen is what defragging is all about.2

But do I need to defrag?

In the past, the answer was a pretty clear yes, but that answer is changing.

  • Solid State Drives (SSDs) should not be defragmented. The “tiny delay” in our example above and the real delays in traditional hard disks have to do with the physical movement of the disk read/write head over spinning magnetic material. Movement takes time. In SSDs, there is no movement, and there’s actually no practical advantage to sectors being logically adjacent. Flash memory wears out the more you write to it and not only does defragmenting write to the disk a lot, but the technologies used in flash-based drives to spread the wear and tear over the entire device also often hides the actual physical location so that sectors that might appear to be adjacent actually are not.3
  • Windows 7 does it for you. Beginning in Windows 7, there’s an automatically scheduled weekly task to defragment your hard disks. Once a week is just fine and you need do nothing more.

Manually defragging

Manually defragging your hard disk is easy.

Start Windows Explorer (Windows Key + E, or right-click on My Computer and click Open), right-click on the drive you want to defrag, click Properties, click the Tools tab and then click Defragment Now….

That’ll open up the Windows Disk Defragmenter:
Windows 7 Defragmenting Tool
In Windows 7, you can also adjust the regularly scheduled defragmentation here. Note that my two drives are 0% fragmented, meaning that all (or most all) files are not fragmented. That’s simply a result of the automated task run by Windows 7.4

You can analyze the fragmentation of a drive or you can actually defragment the drive using this tool.

There are also third-party defragmenting tools that can be used. One such example is Piriform’s Defraggler. Windows’ own tool is typically more than sufficient, but outside tools may provide more information or may be able to perform a faster or more thorough defragmentation.

This is an update to an article originally posted : July 16, 2004

Footnotes and references

1: Technically, the information is grouped in “clusters” of sectors, rather than individual sectors. But for purposes of this discussion, the difference is immaterial.

2: It’s worth noting that because of the small amount of free space left in our example, defragging may or may not be possible, depending on the tool used. While theoretically it should be possible by shuffling individual sectors around, most tools require enough free space to contain at least the largest file being defragmented.

3: Although I do recall reading an analysis that seemed to indicate that defragging an SSD did indeed improve performance slightly. My recommendation remains <strong>don’t do it</strong>. To me, the risk of wearing it out sooner is too great compared with the small performance improvement that might (or might not) be had.

4: I have two physical drives that Windows defragments once a week. The other two are mounted TrueCrypt volumes, the contents of which I should probably defrag as well.

There are 84 comments:

  1. Andrea Moore Reply

    Performance and Maintenance is not in control panel in my Windows XP. Task scheduler is in Programs/Accessories/System Tools. The command c: >c:defrag.log 2>&1 did not work when saved as c:defragit.cmd and entered as a new task from the browse list. Do you have any other suggestions?

  2. Leo Reply

    The full command to run is “defrag c: >c:defrag.log 2>&1″. (And yes, Task Scheduler shows up in different places depending on whether you’re using default, or “classic” start menu.)

  3. deloris cousin Reply

    If you do not defrage your PC, then what is the worst possible thing that can happen?

  4. Questionable Content Reply

    I’m defragging my computer as I type this. But lately, I’ve been getting beaten up by dozens upon dozens of spyware and malware. I run Spybot – Search & Destroy and AdAware, but it seems everytime I scan again some of the same programs are there. Will defragging help me get rid of some of these programs? Will it affect their getting on my computer or their affect on it at all?

  5. Leo Reply

    Defragging will help your computer run more efficiently, but will have no impact at all on spyware or virus infestations. For spyware particularly, the only real defense is, as you have been doing, running a spyware scanner periodically, and avoiding the sites and software that carry spyware when you can.

  6. Dan Hoagland Reply

    I tried to defrag C: using the Executive Home freebie, but got error message, “clusters too big, must be no larger than 4K.” Will any defragger do this?
    (Previously I said “4M”)

    Thanks

  7. Simcha Reply

    It seems to me that defrag in Windows 2000 doesn’t work from the command line. In my office we found a product called Autodefrag which will automate running the Windows Defrag in graphical mode. You can get it here: http://www.morphasys.comautodefrag.

  8. rabbit Reply

    How large is the log file going to become that is being created giving the results of defrag?
    Does this overwrite with each scheduled defrag or will it over time consume lots of space?
    Excuse if this is a silly question, I’m a novice.

    Thanks for a great article.

  9. Leo Reply

    Actually in the example above, the file is created anew each time. Not sure how big it’ll get, but you can get an idea by running it once.

  10. rabbit Reply

    Along the lines of my earlier question about the size of the log file, is it possible to get it so it has a date stamp.
    It reports the defrag was done, but I would like for it to post the date/time of the defrag.

    BTW, this trick automated defrag perfectly and now reports 0% defrag. Thanks.

  11. Leo Reply

    defrag will not, but you could add the following lines to the sequence:

    date /t >>c:defrag.log
    time /t >>c:defrag.log

    The double greater-than signs cause the test to be appended to the log.

  12. jean Reply

    I have tried to defrag my pc 3 times so far and it ran for over 8 hours each time but never left the 0% complete and when I click on show details, I just see a blank white screen. I have never defragged my pc before.
    How long should I expect it to take?

  13. Leo A. Notenboom Reply

    Much less than that, for sure. You didn’t say what operating system version you are running. (“blank white screen” makes me wonder – that’s not how the XP defragger looks).

    What happens if you run a Command Prompt, and then in that prompt, run:

    defrag c:

  14. VMO Reply

    I am having Windows 98 SE. The Defrag does swiftly all the other Drives like D, E & F but not Drive C. I wait and wait and wait nothing seems to happen. Recently I kept the system on for more than 6 hours; still no result. I have used the command option also in vain. Please help.

  15. jake Reply

    after i defragment i still have more then half thw bar in fragmented files,
    File fragmentation
    Total files = 131,712
    Average file size = 624 KB
    Total fragmented files = 3
    Total excess fragments = 16,451
    Average fragments per file = 1.12
    yeah then theres,
    Fragments File Size Files that cannot be defragmented
    395 14.64 GB Documents and SettingsJakeLocal SettingsTemp~GLH0004.TMP
    16,064 18.48 GB Documents and SettingsJakeLocal SettingsTemp~GLH0005.TMP
    i dont know how to get rid of those can you please help me?

  16. Duane Reply

    Many, many moons ago I spoke with a tech who insisted does not *ever* need to be defragged and, more specifically, should *never* be defragged. I’ve defragged at least once a week for well over 10 years; I suppose he was wrong??

  17. Carl Reply

    I defrag regularly (once a week). Seeme to make the system more “compact” every time I do it. Plus, it helps – it really does. Sunday is my “computer maintenance day” LOL. As for “Mary” who is still runnig 98 – time to upgrade to an OS from THIS century!

  18. Ben Lacey Reply

    whenever i defrag, i click the “view report” button after it has finished and it has said for the last couple of weeks that 5% is still fragmented; the programme/file that is is:
    C:Program FilesMicrosoft AntiSpywareerrors.log
    and it has 16,923 fragments and is 4gb big, what should i do with it and is it a “vital” file?

  19. Leo Notenboom Reply

    I would update to Windows Defender (that’s Microisoft AntiSpyware’s new name and new version), uninstall Microsoft AntiSpyware and simply delete the file.

  20. Leo Notenboom Reply

    Nope. Defragging is transparent to your installed software.

  21. huyn Reply

    After I defraged C: drive using windows disk defrag facility,there is a report of the files that can’t be defragged. However, the names of those files are shortened/incomplete and I don’t know how to see the whole file path so that I can get rid of them. I used window xp home. How can I enlarge the report box or get the complete namepath somehow? I tried to print it, but it did not help either. Thanks.

  22. lulu Reply

    well leo, nice to read you article bas i have problem in doing such thing,, am asking about the temporary files, whats will happens if i deleted them?
    will i lose info ??
    thanx

  23. Brent Reply

    I ran defragment on my external hard drive and it came back with alot of file fragmented and clusters.What can I do to get rid of them?

  24. Paul Reply

    HI,
    Can you defrag too many times? I notice that there seems to be and increase in fragmentted files if I repeatedly defrag.

    Thanks.

  25. Leo A. Notenboom Reply

    —–BEGIN PGP SIGNED MESSAGE—–
    Hash: SHA1

    Other than wear and tear on your hard drive you can’t really defrag “too much”.
    I now recommend once a week.

    If you’re seeing more and more defragmented files, it’s typically a function of
    how you use your machine and the effectiveness of the particular defragging
    software you use.

    Leo
    —–BEGIN PGP SIGNATURE—–
    Version: GnuPG v1.4.6 (MingW32)

    iD8DBQFGV2vHCMEe9B/8oqERAstsAJ9K0x8cnQzXMua0FDBS0s9VjE6WrQCdH17O
    l73QDzyaXsr7ki/9AGpDQPg=
    =ykw1
    —–END PGP SIGNATURE—–

  26. windsor Reply

    Nice Article Leo.I’d like to compare fragmentation to a person running continuously to pick up different packets from different places, it would certainly make him whole lot more tired than if he were to go pick it up at once from a single point! I wonder why there is even a debate whether fragmentation affects systems or not.I cannot imagine servers performing at their best if this disease were to afflict them.

  27. stephanie Reply

    I defragged my father’s system and it will not boot up now. It starts in dos mode and tells me that the system is too fragmented and then prompts me to uninstall recovery genesis and defrag my disc. Can anyone help me, please?

  28. Jordan Reply

    Leo, I set my computer to defrag the other night, and it got hung up on a video file at 26%. So, I deleted the video, and it got stuck again at 13% on a different video file. A third attempt and it got stuck at 6% after 8 hours of running on yet a different video file. What do you think I should do, besides not storing too many movies on my hard drive? Thanks.

  29. Kevin Chan Reply

    Hi Leo,
    I find this article quite informative, I never knew that there is such an option available and I am the computer guy at my house. Anyway, I wanted to ask about the task scheduler, so let’s say I did everything like you said; would the computer simply turn itself on and perform the defrag?

  30. Leo A. Notenboom Reply

    —–BEGIN PGP SIGNED MESSAGE—–
    Hash: SHA1

    No, you must leave your computer turned on for scheduled
    tasks to run.

    Leo

    —–BEGIN PGP SIGNATURE—–
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    ftSIh/gGlmGHky2YnZ0X2pM=
    =Xkxo
    —–END PGP SIGNATURE—–

  31. Ness Reply

    Wow, this is really informative. I don’t think I would have gotten a simpler explanation anywhere else. Now I think I will go and do some defragging. Thanks.

  32. John Barron Reply

    My wife ran defragment and now many of the programs are not working properly. My I-tunes keeps searching for the file to open and never opens. Please help.

    Thanks

    John

  33. troy Reply

    Do your comments about defragging also apply to the program “registry optimizer”?

    Thanks
    Troy

  34. Leo A. Notenboom Reply

    —–BEGIN PGP SIGNED MESSAGE—–
    Hash: SHA1

    No. This article applies to registry cleaners and
    optimizers:
    http://ask-leo.com/whats_the_best_registry_cleaner.html

    Leo

    —–BEGIN PGP SIGNATURE—–
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    =lmni
    —–END PGP SIGNATURE—–

  35. Brad Reply

    Thanks alot Leo. I seen my optimizer say that it was reccomended for a defragmentation and i wanted to know what i was doing first. Thankyou!

  36. anonymous Reply

    hi.. do we need to power on our pc if we schedule to defrag at night or early in the morning even if we’re away from our pc’s? thanks..

    Nothing will happen unless the PC is turned on.

    -Leo

  37. Sas Reply

    Excellent article, extremely helpful.
    But I’m having a problem, I can’t save the Notepad file because it’s saying I need permission from the Administrator or something. But my user account *is* the Administrator account on my machine? I’m running Vista if that helps… Thanks!

  38. Rajinder Reply

    hi LEO sir, really very beautifully written that even a layman like me can also understand.humbly saying sir i am very impressed.easy to understand means you have done a lot hardwork thanks a million sir.

  39. Raymond Anderson Reply

    Defragmentation is complete for: HP_PAVILION (C:)

    Some files on this volume could not be defragmented.
    Please check the defragmentation report for the list of these files can you tell me why this comes up and the defragmentation does not finish? Thank you

    Defragging can fail on certain files if they’re too large (not enough free space on the drive), if they are system files, or in some cases if they are in use and locked. You’ll have to look at the log that the messages it telling you about to see what files are not defragged.

    And for the record: it’s ok if some don’t. I wouldn’t worry about it.

    - Leo
    22-Sep-2008
  40. iamawriter Reply

    I have Windows ME. (There is no “manage” box when right clicking on “My Computer”.) How do I perform this operation?

  41. Terry Reply

    when using defrag it brings your computer back up to the speed it was when new not faster

  42. Rohn Reply

    Couple of points of clarification.
    Defrag CAN free up some space in 2 ways. But you shouldn’t count it happening, or expect much space to be freed up.
    First, depending on how the fragmentation happened, each fragment could have “freespace” intended by the file system for growth. So when the file is defragged the only freespace left is at the end of the file.

    The other way defrag can free up space is if there are many small unsed spots on the drive, the file system may not use them until they are “joined” together into a larger block of freespace.

    On the question of locked files, the more “advanced” (than the stripped down defrag tool bundled with Win) defrag tools that can handle locked files. They perform defrag in several discrete steps. One of the later steps is to do a reboot and run a defrag BEFORE the OS and/or “startup” apps are loaded.

    As well, when HD free space is less than 20% Windows can get twitchy. Strange, unexpected, things can happen such as defrag programs abending unexpectedly. It’s not as common a problem these days as it was when HD size was measured in MB not GB.

    I’m afraid you’re incorrect. Defrag does not free up space. The examples you quote are not how things work. Moving free space around does not create more free space.

    - Leo
    17-Jun-2009
  43. ruman Reply

    I defragmented my drive and it improved the speed a lot. I used the trial version of Diskeeper09 which a friend suggested. Its really easy to use as its automatic.

  44. Dee Reply

    I have Vista and the when attempting to save as c:defragit.cmd, a box pops up stating “you do not have permission to save in this location. Contact the administrator to obtain permission.”
    What does this mean and how do i obtain permission?

  45. damnic Reply

    \john system is not accessible you might not have permission to use this
    network resourece.contact the administrator of this server to find out if
    you have access permissions.the server service is not started..

    this errore coming my network pc… what solution
    ..reply me…

  46. Mahesh Reply

    defragment works but sometimes, it also creates problem especially with videos. wats the problem

  47. cameron Reply

    I would seriously recommend the “Piriform Defraggler” for this, free to download and a really good programme, they also have a Ccleaner which cleans out spyware and generally makes your computer run faster, just google piriform if your interested, really good stuff!

  48. Nancy Gardner Reply

    Hi Leo, you’re so wonderful. Thank you. After I defrag and when I view the undefragged files, it just says they’re in my documents but doesn’t tell me which ones. How do I find them?

  49. Nancy Gardner Reply

    Also, maybe you can answer both of these at the same time. I have another computer that will defrag, but there’s a great deal of free space in between the compressed files. Why?

  50. rajesh Reply

    how will i defragg my computer, as it has some problems with my computer. please can u let me know as soon as possible.

  51. Louis Reply

    My personal opinion is that defragging daily is way unnecessary…maybe monthly at most? Piriform’s Defraggler program is great. Just my 2 cents. :)

  52. Yeppers Reply

    Leo, is it safe to defrag an encrypted portable hard drive? If it is safe, should the drive be un-encrypted first — before starting the defrag process? Thanks…

    It depends on the encryption being used, but in general it should be safe. I wouldn’t bother un-encrypting. (As with all things, if you feel there’s possible risk make sure you have a backup of everything.)

    Leo
    01-Aug-2010

  53. Jeody Reply

    Great advice, but..
    It is a bad habit to leave your computer on overnight. Not only does it harm the environment by unnecessarily draining electricity, you harm the computer by having it constantly powered on. Give your computer a break, and save yourself some money. Turn it OFF when you are not using it.

    To be clear you do NOT harm your computer by leaving it on overnight.

    Leo
    13-Nov-2011
  54. Kevin Reply

    Hi Leo
    Good article and mostly good posts.
    But instead of putting my 2 cents worth in (Europe now too!!).
    I would like to ask one question which has intrigued me for some time now, as you have dealt more or less with this question before.
    How can defragging, even once a week wear the HDD out more than the Head flying round like a maniac every time the computer is run. Just can’t visualize it !!!

    Defragging isn’t about increasing or decreasing wear. It’s about improving performance/speed. (Though I would expect that **depending on how the computer is used** defragging once a week, and all the head movement it entails, could reduce wear by reducing the amount of head movement that has to happen in the intervening week.)

    Leo
    26-Oct-2012

  55. Snert Reply

    When I’m doing a lot of video editing I defrag at the end of the day. I use Auslogic’s defragger and it has a Turn Off Computer When Finished check box. I like to chop videos up and splice parts together to see what I can make and that scatters parts of files all over.

  56. KNRover Reply

    While Win 7 does have a built-in defragger, as did previous Windows versions, and it is by default set to run once a week, it is ABYSMALLY slow. For reasons that are obscure to me, it goes thru multiple “passes”; pass after pass after pass. . . A simple defrag can take an hour and impacts your computer’s performance if you’re doing something while it’s running. So I disabled it and installed Auslogics Disk Defrag, which does the same job that the Win 7 defragger does in about 3 minutes. I provide tech support to a dozen families, and do the same on their computers. In short, I recommend against using the Win 7 defragger and instead using the Auslogics product, which is free.

  57. surry roger Reply

    Two items,
    1) re: powering off the PC, In 25 years repairing IBM mainframes, more bugs showed up at power on/off than during normal operations, probably due to power spikes in the associated hardware and disc spin up after the heads had sat a while. I leave mine (PC) on unless it’s going to be days till used.
    2) My friends swear by defrag, and I know the principles well, but I have never seen XP, Vista, or W7 tell me to defrag when I check the status of the spindles, nor have I seen improvement if I did so anyways. Interesting subject ~
    Oh, and I use defraggler (free) if I do -

  58. Darren D Reply

    Wow, OK, defragging… I can finally explain it to easirer my family and freinds, Thanks again for the continuing pearls of wisdom Leo !!!

  59. Bertieboy Reply

    I have an iMac using Mountain Lion – should I use a defragger? I have yet to find one.

  60. Mark J Reply

    @Bertieboy
    Many people say that Macs don’t need to be defragged. (Many also say that Macs can’t get virus and lot of things like that). Not being a Mac expert, I have no idea if this is true, although logically speaking, all OSs have disk management systems which split the files into several locations, so I can’t imagine fragmentation not being an issue on a Mac. iDefrag has a good reputation, but as I said, I don’t have any experience with it so I can’t vouch for it. Maybe some others out there have some experience.

  61. Kevin Reply

    While I agree totally with Leo that the average span for Degragging is 1 week, the in depth answer has to be along the lines of “How long is a piece of string” scenario.
    Every user will be different, and most users will differ from time to time. Main factors are install/uninstall or even restoring an image backup.
    Although all App’s that I have seen give some indication or guidance, I do myself stick to Defraggler (Piriform). When using this I just click Analise first. If the figures are low I do not defrag and therefore reduce HDD wear and tear. If the figures are high I do defrag and paradoxically also reduce HDD wear and tear. Whole thing just takes a little practice. When that done try out the advanced options. These to me speed up the comp. even more.
    Luck All !!!

  62. steven Reply

    Isn’t this really old news, I thought everybody knew about defragging hard drives, since the days of MS-DOS. Use auslogics on demand defragger, no schedules for me. I never practiced the idea of leaving anything on when I am not using it and my hard drive is just fine(for now).

    It’s interesting – in a very real sense this is “old” news, with two caveats, maybe three: 1) new people are coming to computing every day, so it’s new to them, 2) somehow I’ve seen even people who’ve used computers for years not realize it, and 3) things like SSDs and the fact that Windows 7 does it for you is definitely new. But yes, I did think twice about this before I revised the article.

    Leo
    27-Oct-2012
  63. Dom Reply

    Leo,
    Your on-line information is excellent and very helpful to an old “DeePee-er” like me. (circa 1965-1999)
    Question on your use of sectors below:
    2: It’s worth noting that because of the small amount of free space left in our example, defragging may or may not be possible, depending on the tool used. While theoretically it should be possible by shuffling individual sectors around, most tools require enough free space to contain at least the largest file being defragmented.

    I believe that you may have meant to say ” files shuffled”not sectors. Aren’t sectors physical characteristics of a disk (eg. 256KB) permanently arranged for data input? Thank you.

    Files are contained in sectors on the disk, and defragging is, ultimately, nothing more than shuffling the content of sectors around.

    Leo
    27-Oct-2012

  64. Mark J Reply

    @Dom
    I believe when Leo said shuffling sectors around was referring to shuffling the contents of those sectors. Not an error, just another way of looking at it.

  65. adam Reply

    I would like to thank you for all the time you take helping people like me ( 69 year old) who are forever having to get to grip with the computer. Just keep dolng what you’re doing. Those smart!!!!!guys don’t need you but we do.
    Thanks Leo.

  66. Charles Z. Reply

    Thanks for all the information
    Although I know a number of compputer people and work for a large firm with an IT deparment
    Information or explanations are not always freely given. It’s more like they are a secrete societe and the information is not available to us mortals.
    Thanks again, keep up the good work

  67. jack Reply

    If Windows 7 runs defragging automatically once a week, does that mean that if you buy a solid state hard drive you should turn the automatic defragmenting off, if you can?

  68. Mark J Reply

    @Jack
    Windows 7 and 8 turn off automatic defragging if they detect an SSD drive.

  69. Robert Reply

    I’ve been told that you do not need to defrag a Mac. Does Mac have an SSD?

    I see no utility for defragging.

  70. Mark J Reply

    @Robert
    Macbook Air is the model with an SSD.

    Actually the newer MacBook Pros have SSDs as well. In fact I’m typing on one. (No idea on defragging for Mac’s I’m afraid.)

    Leo
    30-Oct-2012

  71. Debbie Reply

    In the example picture of your Disk Defragmenter, when I open mine up like that, it always shows that my C drive is fragmented and that number keeps increasing, right now it’s at 34%. But I cannot analyze it or defrag it. Is there a reason for that happening? Should I be able to defrag the C drive? And why does it keep increasing like that? I’m afraid of what will happen when it gets fuller.

    It’s not a measure of fullness, it’s a measure of how fragmented the files are. Has nothing to do with the space they take up. I’d have to know what happens when you try to defrag to have any suggestions on why it’s not working.

    Leo
    31-Oct-2012
  72. Debbie Reply

    The other drives defrag properly, whether with the automatic scheduling in Windows or if I do it manually, although they usually are never more than 2 to 5% fragmented. However, when I click on the C Drive, even to analyze it, nothing at all happens. The same for when I try to defrag it. And then the next time I look at that window, I see the percentage has usually risen by a couple points on the C drive. Should I be able to defrag the hard drive? How do I get that 34% to zero out again, or does it even matter?

  73. Michael G Reply

    I wonder about the process of disk fragmentation. I am constantly in need to defragment a disk. It seems a scam? I defragmented my disk, did some work, and 155,000 files were immediately fragmented. How are files written? It seems that it is not done in any coherent, intelligent way. Is it a Windows problem? Do ext3 disks suffer this problem? Are files written to the first available space, regardless of how many pieces they will be in, or are they written to the largest free space that will contain them? Do multi-core CPUs write multiple files at once, thus guaranteeing fragmentation? I use Adobe products, eg, Lightroom. that’s the program that left me with 150k fragmented files when I created many 1:1 preview files…

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