Comments on: Disk Fragmentation & OS X: When Does it Become a Problem?

By: B

Tue, 14 Dec 2010 03:21:59 +0000

OSX does get fragmented. Windows more so but most users dont ever have to defrag as vista does it for them. Even if it did not most users would only have to do it every few months to improve disk performance. I have a mac and tried to like the os but could not.

By: Mario

Mario — Mon, 10 Aug 2009 15:03:51 +0000

Claiming that fragmentation (note it’s fragmentation and not defragmentation) is not a problem with OS X is ignorant. Perhaps if you know a bit of CS theory and how any file system works, you would know that fragmentation is inevitable on any file system. You can mitigate some of it (at a performance cost), but you can not completely eliminate it. Depending on your usage patters as well, it may not be a significant problem for you. If you mostly listen to music and browse internet, then don’t worry about it. IF you work with large video files and/or images, then it may be a problem for you.

Perhaps the following Wikipedia article might help to elucidate the issues:

http://en.wikipedia.org/wiki/File_system_fragmentation

In any case, of all the mentioned tools, I find iDefrag the best.

By: alex

alex — Sat, 08 Aug 2009 23:15:37 +0000

I can NOT resize my partition in order to create a 2nd partition (so I can dual boot osx and linux)…I WOULD call that a problem!!!!

(and i have no external drive, etc. in order to fix this problem a different way)

By: Jason

Jason — Sat, 11 Jul 2009 10:35:35 +0000

*** The main reason Linux never needs defragged is partially because of the SWAP partitioning system it uses. In addition to the system partition, most Linux users also use an additional and separate “SWAP” partition, which I have found helps prevent free-space fragmentation, and most Linux distros, like OS X, defrag fragmented files upon opening to prevent file fragmentation. For more information on Linux SWAP see: http://en.wikipedia.org/wiki/Paging#Linux

By: Jason

Jason — Sat, 11 Jul 2009 10:27:50 +0000

Those saying defraging in OS X is never necessary don’t know what they are talking about. For those of us who delete, rewrite, move, etc files extremely often, like me (programmer and web designer) have to defrag once or twice a year, and there is an extremely big difference in performance when I do so. The ONLY OS I have EVER used that never needed defragged is Linux. Been using Linux for close to 10 years. Been using OS X sense the first release. I also run a computer with Windows, and yes, Windows does need defragged a lot more, but OS X still needs it from time to time.

By: Miscellaneous Ramblings....

Miscellaneous Ramblings.... — Mon, 25 May 2009 05:11:30 +0000

Mac: SuperDuper to the Rescue…

Of late, my MacBookPro has been going slower and slower, to the point of being almost unusable due to severe and continual disk swapping. It seems (despite what various pundits say) that my disk was severely fragmented – despite having close to 30 GB…

By: Andy Dent

Andy Dent — Wed, 06 May 2009 14:52:53 +0000

For everyone who says fragmentation is a non-issue on OS/X, you are wrong and I have proven it and comprehensively documented the problem. Small files heal themselves but free-space fragmentation is a very real problem.

If your free space becomes significantly fragmented then the on-the-fly virtual memory file allocation on OS/X gets into deep trouble. I have recorded a swapfile in over 6,000 fragments. System performance improved noticeably after defragging.

Picture of the report and links to even more detailed discussion at http://aussiedesignedsoftware.com/blog/?p=94

By: Andrew Bednarz

Andrew Bednarz — Thu, 23 Apr 2009 21:15:45 +0000

lazyj, it sounds like you should do a full disk check before anything else with Disk Utility. You may need something more powerful like Disk Warrior to repair and rebuild your disk before you keep trying to defrag.

By: alexanderklar

alexanderklar — Wed, 22 Apr 2009 17:03:05 +0000

Thanks for the hints, especially the tool hsfdebug and the reminder to delete caches before defragging. I chose the cheapest path and did a last TimeMachine backup of my hard drive, rebooted from my Leopard DVD, ran the “restore hard drive” menu option, which formatted my hard drive quickly and copied all my files and the entire system nicely organized back onto the disk. This only took about 90 minutes. My MBP runs smoothly now and I could finally install Boot Camp. I am really wondering why I waited over a year before daring this step.

By: lazyj

lazyj — Mon, 20 Apr 2009 23:16:25 +0000

I also got this error: http://www.quicksnapper.com/files/2551/50780900749ED0217ED9D8_m.png

By: lazyj

lazyj — Mon, 20 Apr 2009 22:53:54 +0000

Should one enable “compact b-tree files” under the COMPACT and METADATA tabs in the preferences?

By: Andrew Bednarz

Andrew Bednarz — Mon, 20 Apr 2009 21:41:41 +0000

lazyj – I’ve only tried iDefrag, and it worked really well for me – plus its pretty cheap.

By: ex2bot

ex2bot — Mon, 20 Apr 2009 21:31:41 +0000

Re: Which app to defrag

LazyJ, if you don’t already have a disk utility, I’d recommend you consider either Techtool Pro (which also does defragmentation) or DiskWarrior plus iDefrag. iDefrag may be the best because it can do hotfile clustering, which can improve disk performance. I’m not sure if TechTool Pro has that capability.

Bot

By: lazyj

lazyj — Mon, 20 Apr 2009 20:39:12 +0000

out of the apps listed above, which is most recommended to defrag? I’m definitely exhibiting slowdowns from file space fragmentation.

By: links for 2009-04-19 « 個人的な雑記

links for 2009-04-19 « 個人的な雑記 — Sun, 19 Apr 2009 22:02:25 +0000

[...] Disk Fragmentation & OS X: When Does it Become a Problem? (tags: tools apple performance storage macosx defrag fragmentation disk harddrive mac) [...]

By: fahirsch

fahirsch — Sat, 18 Apr 2009 00:28:31 +0000

Most people don’t need to defrag their macs. In my experience people who do fall in to two groups: a) people with old macs and small hard disks and b) people that work in design and do a lot of work, creating and destroying files and filling the disk.
Some may say that that group a) people should buy new macs. That may be true in the United States . In the rest of the world, not.