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After a lot of hemming and hawing --is that right? -- I finally convinced the original owner to let me have the dang thing already. So, now, I'm getting ready to install Linux on it. I've got a list of software that I want to install and I know what I'm going to do with it. The only thing I need to know now is what file system I should use. Historically, I've gone with ReiserFS, but as that has kind of fallen by the wayside I'd like to look at something else.

The laptop has a 40GB 4200RPM HDD and I'll partition it into four primary as follows: 64MiB for boot, 20GiB for Windows XP Professional, 1024MiB for swap and the remaining space for Linux. I'm looking for a file system that uses space efficiently. I am not sure about journaling, but would that be something I would definitely want on a laptop? It kind of has its own UPS built in, and I am never far from a mains power outlet 99% of the time.

The default file system on most distros these days is EXT3, and I've had good luck with it; that would be my recommendation. While the battery does give you some protection from file system corruptions due to unexpected shutdowns, personally I would still like to have the extra robustness that a journaling file system provides.

If you want to gain a little performance at the expense of robustness, simply disable the journaling and run it as EXT2. You can actually switch the file system back and forth between EXT2 (non-journaled) and EXT3 (journaled) at will, using the tune2fs tool (which AFAIK is included with all modern distros).

What JBI said, and I'd stick with ext3. If the system shuts down suddenly on an ext2 partition, you'll have to ****[1] the drive, which will take many minutes.

I don't think the other major filesystems (Reiser, XFS, JFS) offer anything compelling to laptop users above what ext3 does.


[1] I'll leave this as-is, to highlight the stupidity of the curse filter.

Very nifty, thanks for the input guys. The Gentoo Wiki has a little write up about it too. Supposedly Ext3 is a better performing file system than ReiserFS.

titan wrote:

Supposedly Ext3 is a better performing file system than ReiserFS.

Generally speaking, ext3 is the worst performing of the current Linux journaling filesystems (XFS, JFS, Reiser4) because it's an older design (ext2) with journaling bolted on. It doesn't support extents and it has static inode allocation. They could have made it better if they didn't have the design constraint of backward compatibility with ext2, but ext4 will fix some of these problems. That's not to say ext3 is terrible, but I've found that it certainly lags XFS and JFS in performance on most workloads I personally care about*. Now, I can't say as much about either ReiserFS or Reiser4 because I don't care for them and their performance is somewhat contentious (Namesys's benchmarks vs. others) as well as the quality of implementation. ReiserFS is in the kernel but kind of abandoned and hasn't moved forward architecturally, while Reiser4 is not in the kernel, less proven, and who knows what will happen now that Hans Reiser has been convicted of murder.

One complication in estimating ext3's performance is that ext3 offers several different journal modes: full data & metadata journaling, metadata only with strict ordering between data & metadata writes (ordered), and metadata only without strict ordering (writeback). With full data & metadata journaling, ext3 takes a pretty big hit, but it's actually safer than the other filesystems. XFS and JFS only do metadata journaling and (IIRC) don't guarantee ordering, so with ordered mode, ext3 is safer than XFS and JFS and not terribly slower, depending on the workload.

Personally, I've been using XFS for many years now and keep with it, but I'd go with ext3 unless you have a reason to switch. Space efficiency on all of the filesystems isn't going to be significantly different. ext2 could be faster than the journaling filesystems (with hashed directory indexes enabled, of course), but that's because it's doing less stuff and is less safe. I don't see why anyone would run without at least metadata journaling these days, though.

* I posted some RAID5 benchmarks a while ago with bonnie++ sequential tests with large files comparing XFS vs. JFS vs. ext3 in ordered mode for reference. Obviously this is just one single workload, and probably unrepresentative of a laptop.

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nightmorph wrote:

Unless you go with btrFS or some other new, unjournaled FS (btrfs doesn't need a journal, same for ZFS, which ain't natively available on Linux), you should stick with a journaled FS.

Uh, he'd be insane to go with btrfs considering it's not even alpha quality yet. It says right on their project page, "Btrfs is under heavy development, and is not suitable for any uses other than benchmarking and review. The Btrfs disk format is not yet finalized." There's no guarantee the next update to btrfs will even let you read your existing FS.

It doesn't sound like he's going to be a Gentoo ricer.

Yes, this is a laptop, and the battery is still good. It'll hold out for about two hours.

That is kind of surprising what you guys say about Ext3. Maybe nightmorph should put his two cents in on the Gentoo Wiki article I linked to.

I'd like to make this Gentoo (bthylafh, you should look at my sig for a hint about what my distro of choice is ) installation an SELinux/Hardened version. It's a laptop, and the more secure I can make it, the better. Right? So, attributes are kind of important too. This is a whole new area for me, and I really need something that will not force me to reboot when I discover I need to use a different file system after installing everything.

I know ReiserFS 3.6 supports attributes. (Right?) I am not unwilling to go with ReiserFS, I just want to see if there is a better option out there.

I doubt SELinux is going to make much of a difference in how secure your laptop is. Its primary goal is to contain the potential damage from system services which have been compromised (e.g. by a buffer overflow exploit or malware infection). It does this by explicitly limiting what each program can do to exactly those operations which are required for that program to perform its function.

If anything, a laptop is probably less vulnerable to the sort of security issues SELinux is designed to address, since you're generally not going to run much in the way of externally visible services on it.

titan wrote:

That is kind of surprising what you guys say about Ext3.

Which part is surprising? It's solid and widely used because it's good enough for most people and somewhat of a standard; it's just not the fastest because it retains the significantly older the on-disk structures of ext2 with a journal bolted on.

As far as ReiserFS goes, I really wouldn't recommend either 3 or 4. It's kind of a bad situation because ReiserFS 3 is really showing its age and Reiser4 is out of the kernel, somewhat unproven and has an uncertain future. When I say ReiserFS 3 is showing it's age, some of the reason SuSE ditched ReiserFS are: 1) it still uses the "big kernel lock" for synchronization everywhere, making it scale poorly, 2) it has "serious performance problems with extended attributes and ACLs", and 3) it's in "maintenance mode" and won't be getting new features or new performance improvements so it continues to fall behind other filesystems. At the time of SuSE's decision (two years ago), they said "Ext3’s performance in some situations may not be on par with Reiser3, but it scales better and Andi mentioned the other day that there is quite a bit of research going into improving the locking and general performance of ext3 going on right now, and since reiser3 is stagnant, I don’t doubt they’ll pass them soon."

Frankly, at this point in time, I wouldn't have any reason to recommend either ReiserFS or Reiser4. I'd just go with ext3 or try XFS or JFS if you feel the performance of ext3 wouldn't be sufficient. Of course, that's just my two cents: there's always a slight religious aspect to this -- just like hard drive brands, you can find some people who swear by certain filesystems and swear at others.

I think I'll go with JFS. It seems to be pretty well maintained and it'll perform well, too. I hope.

So I read this thread and found the points about journaled and unjournaled FS's interesting. What I don't really understand is why some of you guys mentioned UPS's and the laptop's battery, although admittedly I did skim. Would that be a battery life issue or what? (Note: I'm not a Linux user, although I have fiddled with it in the past).

if you get a power cut on a machine without a journalled fs you'll probably loose some data.

The Journal adds some redundancy which is way it also slows things down a little.

cheesyking wrote:

if you get a power cut on a machine without a journalled fs you'll probably loose some data.

The Journal adds some redundancy which is way it also slows things down a little.

Actually, the key benefit is not typically about loss of user data. Most of the Linux journaling filesystems only journal metadata anyway (and although ext3 can journal data, people rarely use it because it's just too slow). You can lose data in either case, but the major win is helping keep the on disk metadata consistent. See, many filesystem modifications require several updates to different pieces of filesystem data. If these don't happen atomically (all or none), the filesystem's internal bookkeeping structures can become inconsistent. After a crash or power outage, a journaled FS can use the journal to quickly fix the filesystem metadata. With ext2, the fsck (stupid PHPBB tries to filter the name of the fs check command) program has to scan the whole filesystem and try to fix anything that isn't right. Anyone who's ever sat through a full ext2 fsck on a large partition knows how painful this is.

You can still lose data in journaled filesystems, you just don't have to do a lengthy walk of metadata to figure out how to make the filesystem structure consistent again.

I see. Thanks. Any other benefits of journalling that I should know?

mortifiedPenguin wrote:

I see. Thanks. Any other benefits of journalling that I should know?

Bitvector already pretty much covered it. Bottom line is it helps prevent your file system meta-data from being left in an inconsistent state if the system goes down unexpectedly. This eliminates the need (in most cases) to do a file system check after a power cut or crash.

As an aside, NTFS is a journaling file system as well. That is why Win2K/XP/Vista don't need to check the file systems anywhere near as often as Win9x/ME did (FAT is not a journaling file system).

That reminds, I HATE FAT................ DIE DIE DIE..............

And now I have an issue. I just installed Windows and all of the software that I need on it. The thing is, I forgot to make the partitions for Linux before installing Windows.

You see, I started off by making the partitions with fdisk using the Gentoo Minimal disc. Windows Setup didn't like any of the partitions. Then I remember that Windows demands to be the first partition on the drive. (Stupid, I know, but true.)So, I deleted everything, told Windows to use half the hard drive so I can use the other half for Linux. But I forgot that the way to make this work is to let Windows format its partition then go back into Linux and make the other partitions then go back into Windows and finish the install, then go back to Linux to install that and GRUB.

Anyway, is GParted the answer?

GParted is one answer. I don't have Gentoo experience, but the Ubuntu installer, for example, can resize partitions and create new ones.

bthylafh wrote:

GParted is one answer. I don't have Gentoo experience, but the Ubuntu installer, for example, can resize partitions and create new ones.

Well, I don't need to resize the partition. I just need to add three without ruining all of my hard work. SystemRescueCd to the rescue again!

titan wrote:

I'd like to make this Gentoo (bthylafh, you should look at my sig for a hint about what my distro of choice is ) installation an SELinux/Hardened version. It's a laptop, and the more secure I can make it, the better. Right?

If someone physically gets ahold of your laptop then it doesn't really matter anymore.

FYI, you should change your signature from "The best things in life are free." to "Not everything in life is free."