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On Fri, Nov 28, 2008 at 10:09 AM, Joshua Murphy <poisonbl@×××××.com> wrote: |
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> On Fri, Nov 28, 2008 at 6:46 AM, Alan McKinnon <alan.mckinnon@×××××.com> wrote: |
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>> On Friday 28 November 2008 13:14:42 Dale wrote: |
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>>> If this is a little high, what would be the best way to defrag it? |
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>> |
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>> By not defragging it. |
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>> |
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>> It's not Windows. Windows boxes needs defragging not because fragmentation is |
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>> a huge problem in itself, but because windows filesystems are a steaming mess |
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>> of cr@p that do little right and most things wrong. Defrag treats the |
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>> symptom, not the cause :-) |
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>> |
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>> Reiser tends to self-balance itself out. What is especially noteworthy is that |
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>> none of the general purpose Linux filesystems provide a defrag utility. |
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>> Theodore 'Tso and Hans Reiser are both exceptional programmers, if there was |
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>> a need for such a tool they would assuredly have written one. They did not, |
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>> so there probably isn't. |
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>> |
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>> Any Linux defrag tool you encounter will have been written by a third party |
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>> separate from the developers. It will move blocks around and update |
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>> superblocks, the drive will have to be unmounted for that to work and a |
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>> slight misunderstanding of how to do it will ruin data. |
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>> |
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>> Are you willing to take the very real risk of data corruption? |
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>> |
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>>> Is |
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>>> there a best way? I do have a second hard drive that I back up too. |
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>>> Both Drives are 80Gbs and I do have a set of DVD back ups as well. I |
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>>> can update those pretty quick. |
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>> |
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>> |
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>> |
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>> -- |
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>> alan dot mckinnon at gmail dot com |
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>> |
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>> |
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> |
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> While not trying to incite flames here... xfs isn't general purpose? |
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> xfs_fsr defrags xfs partitions while they're mounted and is designed |
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> to be used from cron (it's in xfsdump, not xfsprogs). File |
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> fragmentation, while a fact of life on any filesystem that sees any |
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> real use, does slow access times, as the drive head has to jump from |
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> one place to another, so a lot of fragmentation is a bad thing... but |
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> as you say, we're not dealing with FAT based FS's here, so severe |
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> fragmentation only shows itself on very full filesystems. I very |
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> rarely see over 80% usage of my filesystems and have never |
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> consistently checked fragmentation levels, though, so I can't say |
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> whether xfs's being the exception on having a tool for the job means |
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> it particularly needed one... |
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|
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I believe JFS has a filesystem defrag tool as well, but I don't think |
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it has a file defrag tool. |
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|
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My favorite way to defrag individual files is to mv to /dev/shm, sync, |
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mv back to hard drive. |
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I've found fragmention to be noticable (as far as slowing disk read |
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speeds) on large files that were downloaded over the internet. Large |
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ISO images, TV shows etc that are hundreds of megabytes downloaded |
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over a long period of time (especially if multiple downloads are |
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streaming at once). On my old "slow" computer (P4 2.8ghz) the file |
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fragmentation on ext3 would get so bad that I could not burn DVD |
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backups of the files at full speed without first defragmenting them. |
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