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Is it time to remove reiserfs?

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Re: Is it time to remove reiserfs?

#211

Post by cestith »

2OEH8eoCRo0 wrote: post #64
cestith wrote: post #29

Personally I've always really liked ReiserFS. The collected storage of small files, the storage of the tails of files, the balanced tree structure, and the fast journaling gave better performance in reads, writes, boot time, and storage efficiency than most file systems. The focus on small files, which were and arguably still are most files on a typical system, was a big key to this. It made it ideal for storing thin…

> The logical successor was supposed to be btrfs, but that project IMHO may never be ready for production use. https://btrfs.wiki.kernel.org/index.php/Production_Users Facebook deployed it on millions of servers. Is that production enough? Synology NAS devices also use it.

Are they using the RAID 5 or RAID 6 code in it? Because that was declared unfit for use well after we were all advised their filesystem was ready for prime time. Then it corrupted and lost data in situations that other file systems did not.

I've heard RAID 1 and RAID 10 modes are safer, but after the FS corrupted my data I haven't really had a lot of trust in it or the people who say again that it's ready for serious use.

Re: Is it time to remove reiserfs?

#212

Post by cestith »

MrDOS wrote: post #193
api wrote: post #83

Earlier quoted context omitted.

Lots of people seem to turn up their nose at btrfs. Is there a reason for that? Was it perhaps launched before it was really ready and people still remember early versions?

AFAIK it's not so bad in single-device use-cases. I think most of the more recent failures I've heard about have all had to do with Btrfs RAID. The prevailing wisdom still seems to be that if you want to use RAID, use an md soft-RAID device or LVM under your single-device Btrfs filesystem.

RAID, especially 5 or 6 was my main concern, yes. If I'm using hardware RAID or a soft RAID under the FS, much of the promised benefit of btrfs is gone anyway. I can add to storage pools with ZFS or expand an LVM set, too, but what does using btrfs on top of anything buy me that ZFS, bcachefs, or something like f2fs does not?

Re: Is it time to remove reiserfs?

#213

Post by cestith »

pnutjam wrote: post #87
api wrote: post #83

Earlier quoted context omitted.

Lots of people seem to turn up their nose at btrfs. Is there a reason for that? Was it perhaps launched before it was really ready and people still remember early versions?

Yes, the only real problems are edge cases. I use it all the time.

What are the equivalent edge cases in XFS, ZFS, ext4, Reiser4, Reiser5, bcachefs, or f2fs that make btrfs worth considering on a level playing field?

Re: Is it time to remove reiserfs?

#214

Post by cestith »

tinco wrote: post #163
Brian_K_White wrote: post #148

Earlier quoted context omitted.

I could already grow mdraid and reiserfs forever ago.

Yes.. but you couldn't grow ZFS. I don't understand what your point is.

Unless Im'm terribly mistaken one could always grow ZFS, but it was via adding more pools.

Re: Is it time to remove reiserfs?

#215

Post by cestith »

TOGoS wrote: post #127
cestith wrote: post #29

Personally I've always really liked ReiserFS. The collected storage of small files, the storage of the tails of files, the balanced tree structure, and the fast journaling gave better performance in reads, writes, boot time, and storage efficiency than most file systems. The focus on small files, which were and arguably still are most files on a typical system, was a big key to this. It made it ideal for storing thin…

I'm no big company, but I've been using btrfs on my Raspberry Pi file server and its disk has been sitting there spinning for something like 8 years with no issues yet. I keep hearing that "btrfs isn't production-ready" but I wouldn't know it from experience.

Perhaps you never lost data from it years after it was billed as ready for use, but many people did. I've never lost data on Reiser3 or Reiser4. I've not used bcachefs or f2fs much yet, but I've never lost data on those either.

Re: Is it time to remove reiserfs?

#216

Post by cestith »

spookthesunset wrote: post #173
5e92cb50239222b wrote: post #166

Earlier quoted context omitted.

> If their machines fail, they don’t care This myth is being perpetuated despite btrfs devs (who work at facebook) stating the exact opposite many times over. Every FS corruption and weird behavior is put aside and investigated. They very much do care. https://lwn.net/ml/fedora-devel/03fbbb9a-7e74-fc49-c663-3272... Please read the whole thread before repeating this nonsense, or at least every email sent there by Jose…

As a tl,dr: “Also keep in mind we pay really close attention to burn rates for our drives, because obviously at our scale it translates to millions of dollars. Btrfs has improved our burn rates with the compression, as the write amplification goes drastically down, thus extending the life of the drives.” As with anything it comes down to money. Yes a machine going down doesn’t impact the cluster but it does impact th…

Do they care about the FS just silently eating data? I ask because btrfs has been known to do that. Sure, you're not replacing the drive, but you're probably wiping the VM's disk image and creating a new one.

Re: Is it time to remove reiserfs?

#217

Post by Lammy »

andix wrote: post #26
DocTomoe wrote: post #22

ReiserFS is a lesson in project naming. When I started in Linux full-time, back in the early 2000s, I was presented with different fs options - the installer did not give me any information on benefits, or on which ones were considered "stable". ext2 was available, but it also had a built-in version number, and I feared that once ext3 eventually rolled over, it might be incompatible. So I chose the fs that came with…

That’s why it’s best to only name things after dead people. Less surprises.

See also: "Butt-Head Astronomer" https://web.archive.org/web/20010720203253/http://idiot-dog....

Re: Is it time to remove reiserfs?

#218

Post by hulitu »

cogman10 wrote: post #82
Frost1x wrote: post #25

ReiserFS is a conversational litmus test I like to casually and indirectly name drop in technical interview discussions surrounding the world of Linux, file systems, and storage to fish and see if someone actually had been actively working in the domain circa 2000ish when there was a lot of hype and criticism bubbling surrounding performance with large sets of small files. Admittedly, it's not a great signal if the c…

Why not update to more modern FSes like BTRFS, XFS, or ZFS? BTRFS, in particular, is pretty heavily inspired by Reiser. I'm not entirely sure what's gained by asking a candidate about FAT16.

Is XFS stable ? I tried reiserfs, jfs and xfs at the beginning and stuck with jfs because reiserfs would eat a lot of processor power and xfs would not run fsck when the power got interrupted which resulted in a corrupted filesystem.

Re: Is it time to remove reiserfs?

#219

Post by ComputerGuru »

5e92cb50239222b wrote: post #166
ComputerGuru wrote: post #138

Earlier quoted context omitted.

Facebook doesn’t use it’s servers the same way we use our computers. They image machines in and out of existence. They don’t have file systems going through power loss on a weekly basis. They don’t upgrade the kernel on existing installations. They don’t expand their storage after the fact. If their machines fail, they don’t care - they’re completely fungible.

> If their machines fail, they don’t care This myth is being perpetuated despite btrfs devs (who work at facebook) stating the exact opposite many times over. Every FS corruption and weird behavior is put aside and investigated. They very much do care. https://lwn.net/ml/fedora-devel/03fbbb9a-7e74-fc49-c663-3272... Please read the whole thread before repeating this nonsense, or at least every email sent there by Jose…

> Every FS corruption and weird behavior is put aside and investigated. They very much do care.

Just because you and I are using different meanings of the word "care" doesn't mean the point isn't valid. They "care" in that they would like to know what went wrong and study it further. They don't "care" in the sense that they suffered no real harm and no stakes were riding on any one particular server that failed. It's not just a matter of having a backup/redundancy, it's about having automated systems (or even just standard procedures that are being executed on a daily basis at that scale one way or the other) that take care of these failures. So even in production, "regular" btrfs users might have backups so "no lasting damage" would be incurred, but that's hardly the same as openly volunteering themselves for risk.

That's all besides the main point: Facebook is deploying "known good" configurations. They're using a very select subset of features. They're not trusting changed btrfs features/implementations being correct or, as was my experience, worrying about less-used/tested codepaths leading to data loss.

Re: Is it time to remove reiserfs?

#220

Post by cogman10 »

hulitu wrote: post #218
cogman10 wrote: post #82

Earlier quoted context omitted.

Why not update to more modern FSes like BTRFS, XFS, or ZFS? BTRFS, in particular, is pretty heavily inspired by Reiser. I'm not entirely sure what's gained by asking a candidate about FAT16.

Is XFS stable ? I tried reiserfs, jfs and xfs at the beginning and stuck with jfs because reiserfs would eat a lot of processor power and xfs would not run fsck when the power got interrupted which resulted in a corrupted filesystem.

It was added to the kernel in 2004. It's stable. That being said, IMO, BTRFS and ZFS are better file systems.
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