Is it time to remove reiserfs? • Hacker News Board

Re: Is it time to remove reiserfs?

#81

Post by cormacrelf » Wed, Feb 23, 2022, 3:53 PM UTC

michael1999 wrote: post #71

marginalia_nu wrote: post #60

Earlier quoted context omitted.

Do zip files really offer performant random access with tens of millions of entries?

I don't see why they wouldn't as long as the TOC (i.e. filenames + headers) fits in ram. The offsets are all there for a simple seek.

Yeah. Tens of millions sounds fine. And you don’t have to keep navigating the raw zip file, you just do it once. “All file offsets available in a single immutable in-memory hash map” is basically the dream scenario. I imagine if you were desperate you could pack more in by representing your file names efficiently in memory, a bit of path compression or a trie or whatever, but if it already works it already works.

Re: Is it time to remove reiserfs?

#82

Post by cogman10 » Wed, Feb 23, 2022, 3:53 PM UTC

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.

Re: Is it time to remove reiserfs?

#83

Post by api » Wed, Feb 23, 2022, 3:54 PM UTC

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.

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?

Re: Is it time to remove reiserfs?

#84

Post by dale_glass » Wed, Feb 23, 2022, 3:54 PM UTC

sterwill wrote: post #61

Syonyk wrote: post #51

Earlier quoted context omitted.

It's great for small files, but it's also got some really nasty little corner cases. You do not store ReiserFS filesystem images on ReiserFS filesystems without encryption, or the next time you run fsck, you'll end up with the two filesystems oddly merged into something entirely useless. I'm not sure if that's been fixed, I got a bit tired of the exotica for general daily driver systems, and ext3/ext4 cover my needs…

That's one heck of an edge case! How does fsck manage to completely confuse filesystem metadata and data like this? Surely this is only if there's corruption in the (outer) filesystem, right?

I think it was the --rebuild-tree argument, which as I understand tries to fix an otherwise completely broken filesystem by searching for anything that looks like metadata and gluing it back together.

I've not looked at reiserfs in many years though, so I could be mis-remembering here.

Re: Is it time to remove reiserfs?

#85

Post by greggyb » Wed, Feb 23, 2022, 3:56 PM UTC

pmarreck wrote: post #57

hughrr wrote: post #32

Earlier quoted context omitted.

Add https://github.com/guardianproject/libsqlfs

I literally discovered this just the other day, the whole concept is extremely intriguing but it hasn't been updated in some time (I'm guessing some forks have been though). Relatedly, it would be pretty cool to be able to build your own filesystem features as layers on each other (such as block-level compression or encryption, block-level forward-error correction, cache promote, striping or other redundancy etc.). A…

Some of what you're describing is in ZFS. E.g., it has multiple compression algorithms; you can create many datasets -- each of these is either a ZFS filesystem or a volume which can have another FS deployed to it, but with compression and encryption handled by the "host" ZFS.

You may also be interested in FreeBSD's GEOM subsystem for storage.

Re: Is it time to remove reiserfs?

#86

Post by pnutjam » Wed, Feb 23, 2022, 3:57 PM UTC

Syonyk wrote: post #51

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…

It's great for small files, but it's also got some really nasty little corner cases. You do not store ReiserFS filesystem images on ReiserFS filesystems without encryption, or the next time you run fsck, you'll end up with the two filesystems oddly merged into something entirely useless. I'm not sure if that's been fixed, I got a bit tired of the exotica for general daily driver systems, and ext3/ext4 cover my needs…

I feel like you really need to have a reason to use ext3/4. I stick to xfs for daily stuff and btrfs if I want any sort of extra functionality. It's super stable in basic configs.

For example, I have a /data drive formated xfs, then I mount a /backup formated btrfs, rsync the 2, take a btrfs snapshot, and unmount /backup.

Re: Is it time to remove reiserfs?

#87

Post by pnutjam » Wed, Feb 23, 2022, 3:57 PM UTC

api wrote: post #83

2OEH8eoCRo0 wrote: post #64

Earlier quoted context omitted.

> 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.

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.

Re: Is it time to remove reiserfs?

#88

Post by amalcon » Wed, Feb 23, 2022, 3:58 PM UTC

prmoustache wrote: post #70

andix wrote: post #26

Earlier quoted context omitted.

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

Well in the case of last name unless those dead peoples was the last one standing with the surname there is always the possibility of a descendant or someone from a different branch of the family name tree commiting bad things. Add to that some people sometimes decide to give a famouse surname as a firstname for their kids. There is a non negligible number of people sporting the Lafayette, Napoleon, Lincoln as first…

Well, it can work out OK if one particular person has a strong enough association with the name. Lincoln is a great example. It seems unlikely that anyone with that name will become so infamous as to tarnish it. The voters of Lincoln, Nebraska or the board of the Ford Motor Company (owners of the Lincoln automotive brand) are pretty safe from needing to rename those things.

Re: Is it time to remove reiserfs?

#89

Post by mcronce » Wed, Feb 23, 2022, 3:58 PM UTC

pmarreck wrote: post #36

mcronce wrote: post #30

Earlier quoted context omitted.

At my previous job, we used reiserfs. We generally referred to it internally as murderfs. Not that I think that's good rebranding, but it did amuse us.

This sounds like it would have been a fun place to work

Honestly it was really great until it wasn't. I was there for almost ten years. The pay left a bit to be desired, but for the most part, everything else was so awesome that it was cool.

Then after some management changes, everything that made it great melted away and we were left with a job that underpays, has poor work-life balance, doesn't appreciate employee time/contributions, etc. It was still a pretty difficult decision to leave; management issues notwithstanding, the group of coworkers I actually worked with every day were - and still are - really great.

Re: Is it time to remove reiserfs?

#90

Post by pnutjam » Wed, Feb 23, 2022, 3:59 PM UTC

fest wrote: post #54

What other filesystems have checksums for data? Last time I looked, after a silent SSD failure that I only noticed because some .so files were affected, the only options were btrfs and reiserfs (I think ZFS required a custom kernel at that time). The incident was really eye-opening in how fragile was my data: if .so files were not affected, I would have continued to use the system and erroneous data would silently be…

I use btrfs with snapshots for my backups. Not only do I get file checksums. The differences in files if I'm hit by ransomware or large-scale file corruption will draw my attention when the disk fills up.