[SOLVED] btrfs Maturity Question

dcbdbis · 2013-10-04 17:24:15

Good Morning All,

I have been following btrfs for over a year awaiting for it to go mainstream. Now I read in several blogs, posts, and other sources that some distro's are considering going with btrfs as the default FS.

I am on ext4, and have a couple of drives that could benefit from the native compression (non system drives). I don't want to convert those drives to btrfs if this new fs is not ready for primetime yet.

In my web crawling, forum haunting, and reading various announcements...I don't sense a consensus of opinion....yet. I see where some are using it, and others where it is causing problems.

I read the nice Arch wiki where it sounds encouraging.....but I would still like to ask btrfs users and others "in the know"......

"Is btrfs a stable FS? Or does it need more time to mature?"

Thank you for your replies,

Sincerely and respectfully,

Dave

Last edited by dcbdbis (2013-10-04 22:47:03)

vostok4 · 2013-10-04 17:40:56

I've been using btrfs without issue on most of my machines, but I don't use any of the advanced features (subvolumes, snapshots, etc). I do use the raid feature, and I need to test out its ability to rebuild arrays as I have a drive failing SMART, so I can finally give some feedback there.

One thing I'm starting to realize is there's not really a big list of "YOU SHOULD DO THIS". It sounds like mounting with -oautodefrag is almost a necessity, or else you need to be defragging your drive consistently as perf can drop off pretty dramatically (like any heavily fragmented drive). There's probably other stuff with reducing the metadata size on a high-use drive (or cleaning it? or scrubbing it? not even sure)... but in general when it works it works well.

I think I would start to use snapshotting on machines that have a measure of importance at some point, as it sounds like a great feature.

graysky · 2013-10-04 18:05:20

It's fine; my root OS is on it. Didn't I read that Fedora defaulted to btrfs or will default in 20?

dcbdbis · 2013-10-04 18:20:39

Thank you for the reply....

I had read that it was Fedora's intention to do so with FC-16. But to date, they still ship with btrfs as an option, but not the default FS. This told me clearly they were holding back for a reason(s) that wasn't specified, or that I couldn't find.

I tend to be conservative with my FS choice, as Arch is my primary OS. I don't want to brick my system, nor brick my data storage archives on /dev/sdb and /dev/sdc. These drives are manually created mirrors of eath other (rsync). If I loose the data on them, I loose 10 years worth of work.

If btrfs gets enough thumbs-up, my plan is to convert one of these drives to btrfs and test. This way if something goes wrong, I can always recreate an ext4 fs on the test drive, and copy over from the remaining ext4 "mirror", and risk nothing.

Then afterwards, I am planning on moving the system drive (/dev/sda) to a 1TB SSD, and I would use btrfs as the default OS when I do a reinstall of Arch onto that new media.

Sincerely and respectfully,

Dave

alphaniner · 2013-10-04 18:39:57

dcbdbis wrote:

If I loose the data on them, I loose 10 years worth of work.

I sincerely hope you forgot about your comprehensive, multi-site, multi-format backups when you made this statement. I wouldn't trust one year of work to drive mirroring or any other RAID[-like] scheme.

Last edited by alphaniner (2013-10-04 18:40:12)

Lynden · 2013-10-04 20:54:13

I've been using btrfs since mid january on my work/daily use laptop.
I haven't run into any problems.. at all. It even survived quite a few hang ups causing me to do a hard reboot.
Scrubbing once a week doesn't expose any errors either, but I have to confess I've never taken the time to do an offline filesystem check.
So maybe there's something hiding, quietly brewing under the surface, but I doubt it xP

graysky · 2013-10-04 20:56:07

Single drive I assume on your laptop? Are there benefits to scrubbing a single drive setup?

WonderWoofy · 2013-10-04 22:28:39

graysky wrote:

Single drive I assume on your laptop? Are there benefits to scrubbing a single drive setup?

Scrubbing can at least tell you if there are files that don't match the checksums. So it can act as a warning if your stuff is starting to experience problems. I actually scrub my btrfs filesystem from time to time (I think it is a weekly cron job), and then check the status when i remember. I did have some journal files go wonky on me, but I then discovered that this is actually a common problem. I "fixed" it by disabling the CoW on /var/log/journal (chattr +C /var/log/journal). This is not really fixing anything though, as disabling CoW will also have the consequence of also having no checksum calculated for those files. So really it is just not reporting anything at all. But they're just log files, and journalctl has the ability to check them anyway… so whatever.

@OP, I use btrfs for my whole system. But I also have tested backups of my system as well. I don't think I would be too distraught if I lost this system anyway and had to rebuild it. Still, for the sake of saving my configs and whatnot, I do back things up to a remote server. It sounds as though you kind of back things up in a way. But what you are doing is not at all what should be considered a safe and sane solution.

I also use many of the awesome features of btrfs, including subvolumes, snapshots, send/receive, etc. These things work great, but bugs do come and go as progress continues at its rapid pace.

You say you are conservative in your choice of filesystem. If that is the case, stick with whatever you have going. Unless you are willing to debug things, and keep a general watch of developments, improvements, and bugs, then you should stay away for now. I believe the experimental flag was removed, but that still doesn't mean that it is entirely problem free (though no filesystem/software is truly problem free). For example, until maybe 3.11.4 (maybe 3.11.5) there is a bug that causes the system to panic when defragging. I don't know if this is both regular and autodefrag, or what, but it is the kind of thing that would probably just confuse the hell out of most users, who wouldn't know that a fix is available, and can be patched in manually.

If you do run btrfs, you should always ensure that you are running the latest stable kernel at the very least (which is easy with Arch), and it is recommended that you run the latest rc from Linus' git tree (usually a sane thing to do after about rc2 or rc3) or build from the btrfs-next kernel branch.

dcbdbis · 2013-10-04 22:58:16

Thank you all for the replies. I appreciate it.

I have enough information now to make a decision about btrfs......

From what I have gathered and what I hear on this forum....btrfs is stable...for the most part....

I heard drive scrubbing still occasionally shows problems and different types of defrag sometimes brings with it issues. Another viewpoint was to run the latest RC from the git tree.

Everyone's responses were helpful and diverse. IE: "Your mileage may vary."

All of this gives me the impression that btrfs is not as mature as I personally would like to have it for deployment on my workstation, nor on my NAS. Not to say it's not working for others, it clearly is.....It is also clear that there are still some remaining "growing pains".

My decision for now, is to stick with the tried and true ext4 to allow more time for some additional polish to be added to btrfs.

My thanks to all for your responses.....It was exactly the kind of confirmation I needed to hear.

Sincerely and respectfully,

Dave

Lynden · 2013-10-04 23:00:43

graysky wrote:

Single drive I assume on your laptop? Are there benefits to scrubbing a single drive setup?

Indeed, a single drive. But as WonderWoofy already said, it can detect errors, but not repair them (There's no parity data after all).
But I find it useful to have as an sort of warning system along side smart. If it starts spitting out lots of errors, then it's probably an imminent drive failure.

Side note: I haven't experienced that log issue, WonderWoofy.

WonderWoofy · 2013-10-04 23:05:35

Lynden wrote:

Side note: I haven't experienced that log issue, WonderWoofy.

It was just once that I had it, and it only reported 1 unrecoverable error. So I deleted the file in question… only to realized that I had snapshots of it. So I deleted those snapshots, and all was fine.

Lynden · 2013-10-04 23:06:42

dcbdbis wrote:

Thank you all for the replies. I appreciate it.
[...]
Sincerely and respectfully,
Dave

Mm, you mention NAS. If it's data storage of non-root drives then perhaps ZFS might be an option for you.
Unfortunately it's not part of the linux kernel, but it's very easy to use thanks to all the helpful people here.
It offers pretty much the same stability as ext4 in my experiences as well as compression, checksumming, etc.

https://wiki.archlinux.org/index.php/ZFS

donniezazen · 2013-10-05 05:54:46

I use btrfs on my system. I have been using it for a long time. I have never had my system crash or have any other problems. I find it no good or bad when compared to ext4. I use it to learn more about it. If you are curious I use subvolume and OpenSUSE's Snapper to automatic snapshot every hour. My primary backup system is to mirror home folder. OpenSUSE shipped it in 12.3 but it will either not install or not boot. I hear they are going to make it default in 13.1.

WonderWoofy · 2013-10-05 06:18:11

donniezazen wrote:

My primary backup system is to mirror home folder.

This is not a backup solution!!!

donniezazen · 2013-10-05 06:56:16

WonderWoofy wrote:

donniezazen wrote:
My primary backup system is to mirror home folder.
This is not a backup solution!!!

“!!!ALL generalizations ARE dangerous, EVEN this ONE.” - Alexandre Dumas!!!!!!.

That being said. It serves my backup needs.

jferreira · 2013-10-07 14:47:57

I do use btrfs for non-system files (1tb drive full of pictures, maya scenes, videos and some workspace backups) and I am pretty disappointed. I have to scrub the FS from time to time otherwise I might end up with the "No space left on device" when trying to remove some files.
Didn't notice any performance improvement compared to ext4. Don't use any fancy features, as a matter of fact, any FS supporting filesizes > 4gb will suit me. The "scrubbing hell" is a downside.
The fact that there are tools provided to defrag and scrub the filesystem show some maturity and reliability to the filesystem, UNLESS you're not the Average Joe. Don't think any distro should default to this FS unless it uses some kind of autodefrag or autoscrubbing, otherwise the average joe (like me) can get frustrated.

Arch Linux

#1 2013-10-04 17:24:15

[SOLVED] btrfs Maturity Question

#2 2013-10-04 17:40:56

Re: [SOLVED] btrfs Maturity Question

#3 2013-10-04 18:05:20

Re: [SOLVED] btrfs Maturity Question

#4 2013-10-04 18:20:39

Re: [SOLVED] btrfs Maturity Question

#5 2013-10-04 18:39:57

Re: [SOLVED] btrfs Maturity Question

#6 2013-10-04 20:54:13

Re: [SOLVED] btrfs Maturity Question

#7 2013-10-04 20:56:07

Re: [SOLVED] btrfs Maturity Question

#8 2013-10-04 22:28:39

Re: [SOLVED] btrfs Maturity Question

#9 2013-10-04 22:58:16

Re: [SOLVED] btrfs Maturity Question

#10 2013-10-04 23:00:43

Re: [SOLVED] btrfs Maturity Question

#11 2013-10-04 23:05:35

Re: [SOLVED] btrfs Maturity Question

#12 2013-10-04 23:06:42

Re: [SOLVED] btrfs Maturity Question

#13 2013-10-05 05:54:46

Re: [SOLVED] btrfs Maturity Question

#14 2013-10-05 06:18:11

Re: [SOLVED] btrfs Maturity Question

#15 2013-10-05 06:56:16

Re: [SOLVED] btrfs Maturity Question

#16 2013-10-07 14:47:57

Re: [SOLVED] btrfs Maturity Question

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