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ZFS fans, rejoice – RAIDz expansion will be a thing soon

arstechnica.com

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Re: ZFS fans, rejoice – RAIDz expansion will be a thing soon

#51

Post by hpfr »

colechristensen wrote: post #21
auxym wrote: post #4

Earlier quoted context omitted.

RAM? Everytime I looked into setting up a freenas box, every hardware guide insisted that ungodly amounts of absolutely-has-to-be-ECC RAM was essential, and I just gave up at that point.

ZFS likes RAM and uses it to get better performance (and don't think about using dedup without huge ram), but you don't need it and can change the defaults. ECC tends to attract zealots after a perfect error-free existence which ECC does tend towards but doesn't deliver, it just reduces errors. I personally don't care about a tiny amount of bit rot (zfs will prevent most of this) and rebooting my storage machine now…

Does rebooting help with soft errors in non-ECC RAM? I would have thought bit flips would be transient in nature, but I'm not really familiar.

Re: ZFS fans, rejoice – RAIDz expansion will be a thing soon

#52

Post by baaym »

the8472 wrote: post #32
d33lio wrote: post #2

I'll believe it when I see it, why anyone uses BTRFs (UnRaid or any other form of software raid that isn't ZFS) is still beyond me. At least when we're not talking SSD's ;) ZFS is incredible, curious to mess around with these new features!

btrfs does have some advantages over zfs - no data duplicated between page cache and arc - no upgrade problems on rolling distros - balance allows restructuring the array - offline dedup, no need for huge dedup tables - ability to turn off checksumming for specific files - O_DIRECT support - reflink copy - fiemap - easy to resize

And even included in the kernel

Re: ZFS fans, rejoice – RAIDz expansion will be a thing soon

#53

Post by nimbius »

this might sound like a troll comment but its coming from someone with almost zero experience with raid. What is the purpose of ZFS in 2021 if we have hardware RAID and linux software RAID? BTRFS does RAID too. Why would people choose ZFS in 2021 if both Oracle and Open Source users have 2 competing ZFS? are they interoperable?

Re: ZFS fans, rejoice – RAIDz expansion will be a thing soon

#54

Post by nickik »

I prefer just to have mirrors but its cool that it slowly coming, some people seem to really want this feature.

ZFS has been amazing to me, I have zero complaints.

I just wish it wouldn't have taken so long to come to /root on linux. Even still today you have to a lot of work unless you want to use the new support in Ubuntu.

This license snafu is so terrible, open-source licenses excluding each other. Crazy. The world would have been a better place if linux had incorporated ZFS long ago. (And no we don't need yet another legal discussion, my point is just that its sad).

Re: ZFS fans, rejoice – RAIDz expansion will be a thing soon

#55

Post by oarsinsync »

tombert wrote: post #28
radiowave wrote: post #26

Earlier quoted context omitted.

Relevant quote from one of ZFS's primary designers, Matt Ahrens: “There's nothing special about ZFS that requires/encourages the use of ECC RAM more so than any other filesystem. ... I would simply say: if you love your data, use ECC RAM. Additionally, use a filesystem that checksums your data, such as ZFS."

Yeah, I remember reading that a few years ago. If I were running a server farm or something, then yeah, I'd probably use ECC memory, but I think if you're running a home server, then the argument that ZFS necessitates ECC more than Ext4 or Btrfs or XFS or whatever doesn't really seem to be accurate.

> the argument that ZFS necessitates ECC more than Ext4 or Btrfs or XFS or whatever doesn't really seem to be accurate

Agreed.

> If I were running a server farm or something, then yeah, I'd probably use ECC memory, but I think if you're running a home server

Then you should still use ECC RAM, regardless of what filesystem you're using.

No, really. ECC matters (https://news.ycombinator.com/item?id=25622322) generally.

Re: ZFS fans, rejoice – RAIDz expansion will be a thing soon

#56

Post by sz4kerto »

nimbius wrote: post #53

this might sound like a troll comment but its coming from someone with almost zero experience with raid. What is the purpose of ZFS in 2021 if we have hardware RAID and linux software RAID? BTRFS does RAID too. Why would people choose ZFS in 2021 if both Oracle and Open Source users have 2 competing ZFS? are they interoperable?

I don't want to be trolling either, but a simple Google search gives you really detailed answers. Or just look at Wikipedia: https://en.wikipedia.org/wiki/ZFS

Some highlights: hierarchical checksumming, CoW snapshots, deduplication, more efficient rebuilds, extremely configurable, tiered storage, various caching strategies, etc.

Re: ZFS fans, rejoice – RAIDz expansion will be a thing soon

#57

Post by mixedCase »

d33lio wrote: post #2

I'll believe it when I see it, why anyone uses BTRFs (UnRaid or any other form of software raid that isn't ZFS) is still beyond me. At least when we're not talking SSD's ;) ZFS is incredible, curious to mess around with these new features!

I just put two 8TB drives into btrfs because it's a home server, I can't provision things up front. One day I may put a third 8TB drive and turn this RAID1 into RAID5. btrfs lets me do that, zfs doesn't, simple as.

One day I may switch the whole thing to bcachefs, which I've donated and am looking forwards to. For the moment, btrfs will have to do.

EDIT: downvoted by... the filesystem brigade?

Re: ZFS fans, rejoice – RAIDz expansion will be a thing soon

#58

Post by wyager »

nimbius wrote: post #53

this might sound like a troll comment but its coming from someone with almost zero experience with raid. What is the purpose of ZFS in 2021 if we have hardware RAID and linux software RAID? BTRFS does RAID too. Why would people choose ZFS in 2021 if both Oracle and Open Source users have 2 competing ZFS? are they interoperable?

ZFS RAID is the best RAID implementation in many respects. Hardware RAID is bad at actually fixing errors on disk (as opposed to just transparently correcting) and surfacing errors to the user.

BTRFS is frequently not considered stable enough for production usage.

ZFS has dozens of useful features besides RAID. Transparent compression, instant atomic snapshots, incremental snapshot sync, instant cloning of file systems, etc etc.

Yes, different ZFS implementations are mostly compatible in my experience, and they should become totally compatible as everyone moves to OpenZFS. FreeBSD 13 and Linux currently have ZFS feature parity I believe.

Re: ZFS fans, rejoice – RAIDz expansion will be a thing soon

#59

Post by tehbeard »

nimbius wrote: post #53

this might sound like a troll comment but its coming from someone with almost zero experience with raid. What is the purpose of ZFS in 2021 if we have hardware RAID and linux software RAID? BTRFS does RAID too. Why would people choose ZFS in 2021 if both Oracle and Open Source users have 2 competing ZFS? are they interoperable?

I can't speak with much experience, but what I have gleamed is.

- You generally want to avoid hardware raid, if the card dies you'll likely need to source a compatible replacement vs. grabbing another SATA/was expander and reconstructing the array.

- zfs handles the stack all the way from drives to filesystem, allowing them to work together (i.e filesystem usage info can better dictate what gets moved around tiered storage, or better raid recovery.

Re: ZFS fans, rejoice – RAIDz expansion will be a thing soon

#60

Post by nickik »

nimbius wrote: post #53

this might sound like a troll comment but its coming from someone with almost zero experience with raid. What is the purpose of ZFS in 2021 if we have hardware RAID and linux software RAID? BTRFS does RAID too. Why would people choose ZFS in 2021 if both Oracle and Open Source users have 2 competing ZFS? are they interoperable?

> What is the purpose of ZFS in 2021 if we have hardware RAID

Hardware RAID is actually older then ZFS style software RAID. ZFS was specifically designed fix the issues with hardware RAID.

The problem with Hardware RAID is that is has no ideas what going on on top of it, and even worse, its a mostly a bunch of closed-source fireware from a vendor. And they cost money.

You can find lots of terrible story about those.

ZFS is open-source and battle tested.

> linux software RAID

Not sure what you are referring too.

> BTRFS does RAID too.

BTRFS is basically copied many of the features done in ZFS. BTRFS has a history of being far less stable. ZFS is far more battle tested. They say its stable now, but they had said that many times. It eat my data twice so I have not followed the project anymore. A file system in my opinion gets exactly 1 chance with me.

They each have some features the other doesn't but broadly speaking they are similar technology.

The new bcacheFS is also coming up and adding some interesting features.

> Why would people choose ZFS in 2021 if both Oracle and Open Source users have 2 competing ZFS?

Not sure what that has do with anything. Oracle is an evil company, they tried take all these great open source technologies away from people and the community thought against it. Most of the ZFS team left after the merger.

The Open-Source version is arguable better, and has far more of the original designers working on it. The two code bases have diverged a lot since then.

At the end of the day ZFS is incredibly battle tested, works incredibly well at what it does. And had a incredible reputation of stability basically since it came out. They question in my opinion is why not ZFS, then why ZFS.

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