Gentoo Archives: gentoo-user

From: Dale <rdalek1967@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Fragmentation of my drives. Curious mostly
Date: Fri, 28 Nov 2008 17:24:18
Message-Id: 49302938.7070307@gmail.com
In Reply to: Re: [gentoo-user] Fragmentation of my drives. Curious mostly by Joshua Murphy
1 Joshua Murphy wrote:
2 > On Fri, Nov 28, 2008 at 6:46 AM, Alan McKinnon <alan.mckinnon@×××××.com> wrote:
3 >
4 >> On Friday 28 November 2008 13:14:42 Dale wrote:
5 >>
6 >>> If this is a little high, what would be the best way to defrag it?
7 >>>
8 >> By not defragging it.
9 >>
10 >> It's not Windows. Windows boxes needs defragging not because fragmentation is
11 >> a huge problem in itself, but because windows filesystems are a steaming mess
12 >> of cr@p that do little right and most things wrong. Defrag treats the
13 >> symptom, not the cause :-)
14 >>
15 >> Reiser tends to self-balance itself out. What is especially noteworthy is that
16 >> none of the general purpose Linux filesystems provide a defrag utility.
17 >> Theodore 'Tso and Hans Reiser are both exceptional programmers, if there was
18 >> a need for such a tool they would assuredly have written one. They did not,
19 >> so there probably isn't.
20 >>
21 >> Any Linux defrag tool you encounter will have been written by a third party
22 >> separate from the developers. It will move blocks around and update
23 >> superblocks, the drive will have to be unmounted for that to work and a
24 >> slight misunderstanding of how to do it will ruin data.
25 >>
26 >> Are you willing to take the very real risk of data corruption?
27 >>
28 >>
29 >>> Is
30 >>> there a best way? I do have a second hard drive that I back up too.
31 >>> Both Drives are 80Gbs and I do have a set of DVD back ups as well. I
32 >>> can update those pretty quick.
33 >>>
34 >>
35 >> --
36 >> alan dot mckinnon at gmail dot com
37 >>
38 >>
39 >>
40 >
41 > While not trying to incite flames here... xfs isn't general purpose?
42 > xfs_fsr defrags xfs partitions while they're mounted and is designed
43 > to be used from cron (it's in xfsdump, not xfsprogs). File
44 > fragmentation, while a fact of life on any filesystem that sees any
45 > real use, does slow access times, as the drive head has to jump from
46 > one place to another, so a lot of fragmentation is a bad thing... but
47 > as you say, we're not dealing with FAT based FS's here, so severe
48 > fragmentation only shows itself on very full filesystems. I very
49 > rarely see over 80% usage of my filesystems and have never
50 > consistently checked fragmentation levels, though, so I can't say
51 > whether xfs's being the exception on having a tool for the job means
52 > it particularly needed one...
53 >
54 >
55
56 Given my experience with XFS, I won't be switching anytime soon. I used
57 that once on a in-laws system. After each crash, power failure, I had
58 to reinstall. Let's just say it left a bad taste in my mouth. ;-) I'm
59 not saying it is a bad file system for someone but certainly not for me.
60
61 You are right tho, every file system has some fragmentation. It just
62 can't be otherwise. I guess I could always make my back ups, then redo
63 my partitions, and copy them back. I have done that once before.
64 Worked very well then but not real sure about how udev would like that.
65 I would think it would work OK but call me chicken.
66
67 Dale
68
69 :-) :-)

Replies

Subject Author
Re: [gentoo-user] Fragmentation of my drives. Curious mostly Joshua Murphy <poisonbl@×××××.com>
Re: [gentoo-user] Fragmentation of my drives. Curious mostly Neil Bothwick <neil@××××××××××.uk>