The Filesystem choice thread

phong · Posted: Tue Nov 05, 2002 1:45 pm Post subject:

I'm making this the "master" filesystem choice discussion thread and moving it to Gentoo Chat. It's become more of a discussion topic than a support question, and I'd like to be able to concentrate all the "which filesystem should I use" discussion to one thread. I've changed the subject of the thread to reflect this, and also made it sticky.

For those who are reading this thread looking for Yet Another Opinion(tm), I'd like to plug Reiserfs. It's stable in current versions of the Kernel (note that Ext3 and XFS have also had corruption problems in the past, and apparently XFS has some problems currently), and it's very fast for large numbers of files. For example, manipulating hundreds of megs of e-mail in maildir format goes very very quickly (tens of thousands of messages can be inadvertantly deleted in seconds!)

Also, reiser4 looks like it will change the world.
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eryvile · Apprentice Joined: 14 Aug 2002 Posts: 234 Location: europe

boyo · n00b Joined: 02 Nov 2002 Posts: 53 Location: MI

45 to 50 MB/s?

For an EIDE drive? What kind of hdd/controller setup does your workstation have?

hook · Posted: Tue Nov 05, 2002 9:20 pm Post subject:

ok, this will sound really dumb, but i think it's an importaint question:
is there a difference between these FSs in the point that some programs don't / won't work under certain FSs?

...i appologise myself again for the stupid question, but i had to ask
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phong · Posted: Tue Nov 05, 2002 9:35 pm Post subject:

Short answer - no. Long answer - maybe, but only if you're into kernel hacking or heavy-wizardry. For the end user, unless there's a bug, the only noticable difference will be performance.
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"An empty head is not really empty; it is stuffed with rubbish. Hence the difficulty of forcing anything into an empty head."
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eryvile · Apprentice Joined: 14 Aug 2002 Posts: 234 Location: europe

KiTaSuMbA · Guru Joined: 28 Jun 2002 Posts: 430 Location: Naples Italy

For the file systems:
I use XFS for the / since I first installed gentoo 1.2 with no troubles at all (mind you, I have experienced inumerous power losses and brown-outs since then). Ext2 and ext3 are also worth their bucks in reliability but are quite more slow. I haven't tried reiserFS since the first versions of 2.4.x kernels (back then it was very unreliable) so I can't refer personally on its current state - people seem very happy with it though...
And now I have a question: do the current gentoo-sources support XFS? I've sticked with the xfs- branch but I would like to try preemptive. Any specific DONTs with using preemptive with ALSA and XFS?

For the hdparm "sub-issue":
My hdb (gentoo) is an ATA100 disk and goes at 34-38 Mb/s while hda (udma66 - windows and slack) goes at about 24-26. I know a faster drive shouldn't be a slave, but windows are rather picky on going for first disks... This will probably change as I'm in desperate need of extra disk space and think of "upgrading" to XP (installing it on a fresh hda, too many have had nightmares with drives containing non windows partitions).
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rac · Posted: Tue Nov 05, 2002 11:36 pm Post subject:

KiTaSuMbA · Guru Joined: 28 Jun 2002 Posts: 430 Location: Naples Italy

So, the -r2 xfs sources have preemptive bundled... I'm using the -r1 right now and didn't notice the options (either there weren't any, or I'm getting blind). Since, I wouldn't like using unstable code on this machine, I guess emerge xfs-2.4.19-r2 is the prefered course of action here...
Thanx for the feedback :wink:

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rac · Posted: Tue Nov 05, 2002 11:59 pm Post subject:

boyo · n00b Joined: 02 Nov 2002 Posts: 53 Location: MI

From what I've checked out it seems that 40-50 MB/s is about right for the upper performance limits of ATA-100 drives and controllers. I've only been able around 35 or so MB/s out of my 7200 rpm ATA-100 WD400BB (40GB w/ 2MB cache) on a Highpoint 370 controller. On paper the WD drive I'm using matches up evenly w/ the IBM Deskstar models, and I doubt my controller makes 5-15 MB/s worth of difference. I'm not doubting your earlier post (eryvile). I'd just love to match it. :wink:

Which hdparm flags are you using?

squanto · Posted: Wed Nov 06, 2002 2:23 am Post subject:

boyo · n00b Joined: 02 Nov 2002 Posts: 53 Location: MI

I'd expect a drive with a larger cache to deliver better performance so I'm not terribly surprised that you're getting the transfer rates you are. Especially since the WD special edition drives also support ATA-133. I'd still like to know how to go about getting 40-45 MB/s with an ATA-100 controller and a 7200 RPM 2MB cache hdd. I thought my hdd was hdparm'ed to it's fullest potential, but apparently not. any tips would be welcomed and appreciated.

Back to the actual subject of the thread...

Does the Reiserfs -notail option have an impact on performance at all? It's definitely a cool feature, but what's it cost?

phong · Posted: Wed Nov 06, 2002 5:34 am Post subject:

Using the "tail" option is more space efficient, but a bit slower (not hugely apparently). The "notail" option is what people usually recommend because it's faster, and even with that, reiser tends to be more space effiecent than the others.
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"An empty head is not really empty; it is stuffed with rubbish. Hence the difficulty of forcing anything into an empty head."
-- Eric Hoffer

eryvile · Apprentice Joined: 14 Aug 2002 Posts: 234 Location: europe

hook · Posted: Wed Nov 06, 2002 7:53 pm Post subject:

ok, ...so the conclusion would be that if you are using your linuxbox as an usual home workstation, you don't have to care about the difference, because you would not get any profit out of it?
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boyo · n00b Joined: 02 Nov 2002 Posts: 53 Location: MI

Honestly, hdparm stats are hardly anything to feel miserable about.

The intent of my question was curiosity, not to discredit anyone. If 45-50 MB/s was mis-read, no biggie. If not give me a hand tweaking hdparm for sure.

Anyway, phong, thanks for the earlier link to Reiser4. The plugin funtionality sounds awesome. Do you have any idea which ones will be availible upon realease? I'll definitely be inclined to give it a try.

squanto · Posted: Wed Nov 06, 2002 9:42 pm Post subject:

boyo · n00b Joined: 02 Nov 2002 Posts: 53 Location: MI

I'm guessing XFS has no such feature. I suppose I'll have to do some additional reading to adequately compare how it manages space in comparison to Reiserfs. I'd be willing to bet that it doesn't have the same degree of flexibility, but there's probably a distinct performance gap between Reiserfs w/ the -tail option and XFS. Do you see any noticeable differences in CPU usage between -tail and -notail?

Thanks for the good info.

squanto · Posted: Thu Nov 07, 2002 3:00 am Post subject:

The default is to run with the tail option enabled, I just found that out. So I have been running all the time with tail on, and writing to disk uses less than 1% of cpu cycles. So I would say that it is pretty good at not using the cpu :mrgreen:

I have had no problems so far with reiser.

metalhedd · Posted: Thu Nov 07, 2002 3:11 am Post subject:

Ok I think It's generally understood that Reiser is the better FS for many small files, but nobody ever specified what is considered "small" are we talking about 5k config files? or 5MB MP3s?either could be considered small

boyo · n00b Joined: 02 Nov 2002 Posts: 53 Location: MI

The "small" range in question is pretty trivial - something like < 10k. Nothing signifigant over XFS with files above that size. Knowing that XFS was built by SGI from the ground up for handling larger media files (mp3, ogg, mpg, avi, images, etc.) is about the only reason it's something I'm still considering (I've read some great stuff about Reiserfs on this thread). Much of my space consuming data consists of those file types, and XFS seems to have the upper hand when dealing with them. phong posted a link to Reiser4 earlier in the thread. Hopefully when I've finished reading it I'll be convinced one way or the other. I have been using Reiserfs, but XFS has always been in the back of mind since I've been quite impressed by it as well. I've been keeping close track of this thread hoping for something distinctly convincing.

pilla · Posted: Thu Nov 07, 2002 4:14 am Post subject:

I first tried ReiserFS when it did not have quota support (too bad I just learned that after installing it).

I am using EXT3 in my notebook (cannot lost data!) and in my desktop, no problems at all until now. We are using it in some servers, too. About performance, I cannot say anything but that it is not slow enough to be a problem for me... I do not have another FS to compare, right now.

EXT3 has the advantage of being widelly supported, any grub or kernel usually can mount at least EXT2 filesystems (and you can mount EXT3 without jornal, which is just EXT2).

boyo · n00b Joined: 02 Nov 2002 Posts: 53 Location: MI

C'mon, Where's your sense of adventure? :wink:

ext3 has done well when I've used it, but that hasn't been as extensively as Reiserfs or XFS (both have been outstanding). Being the performance junkie I am if there's something faster that's not ridiculously unsafe I'm all about it. The mounting without a journal sounds handy though.

lupad · n00b Joined: 13 Oct 2002 Posts: 7 Location: South Africa