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ZFS 2.3 released with ZFS raidz expansion

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Re: ZFS 2.3 released with ZFS raidz expansion

#181

Post by wkat4242 »

cesarb wrote: post #175
GuB-42 wrote: post #73

Earlier quoted context omitted.

To be honest, the situation with Linux is barely better. ZFS has license issues with Linux, preventing full integration, and Btrfs is 15 years in the making and still doesn't match ZFS in features and stability. Most Linux distros still use ext4 by default, which is 19 years old, but ext4 is little more than a series of extensions on top of ext2, which is the same age as NTFS. In all fairness, there are few OS compon…

> Btrfs [...] still doesn't match ZFS in features [...] Isn't the feature in question (array expansion) precisely one which btrfs already had for a long time? Does ZFS have the opposite feature (shrinking the array), which AFAIK btrfs also already had for a long time? (And there's one feature which is important to many, "being in the upstream Linux kernel", that ZFS most likely will never have.)

ZFS also had expansion for a long time but it was offline expansion. I don't know if btrfs has also had online for a long time?

And shrinking no, that is a big missing feature in ZFS IMO. Understandable considering its heritage (large scale datacenters) but nevertheless an issue for home use.

But raidz is rock-solid. Btrfs' raid is not.

Re: ZFS 2.3 released with ZFS raidz expansion

#182

Post by ryao »

formerly_proven wrote: post #167
ryao wrote: post #147

Earlier quoted context omitted.

There is a clever trick that is used to make top level removal work. The code will make the vdev readonly. Then it will copy its contents into free space on other vdevs (essentially, the contents will be stored behind the scenes in a file). Finally, it will redirect reads on that vdev into the stored vdev. This indirection allows you to remove the vdev. It is not implemented for raid-z at present though.

Though the vdev itself still exists after doing that? It just happens to be backed by, essentially, a "file" in the pool, instead of the original physical block devices, right?

Yes.

Re: ZFS 2.3 released with ZFS raidz expansion

#183

Post by bluGill »

poisonborz wrote: post #161
bayindirh wrote: post #127

Earlier quoted context omitted.

> How come that Windows still uses a 32 year old file system? Simple. Because most of the burden is taken by the (enterprise) storage hardware hosting the FS. Snapshots, block level deduplication, object storage technologies, RAID/Resiliency, size changes, you name it. Modern storage appliances are black magic, and you don't need much more features from NTFS. You either transparently access via NAS/SAN or store your…

So private consumers should just pay cloud subscription if they want safer/modern data storage for their PC? (without NAS)

Probably. There are levels of backups, and a cloud subscription SHOULD give you copies in geographical separate locations with someone to help you (who probably isn't into computers and doesn't want to learn the complex details) restore when (NOT IF!) needed.

I have all my backups on a NAS in the next room. This covers the vast majority of use cases for backups, but if my house burns down everything is lost. I know I'm taking that risk, but really I should have better. Just paying someone to do it all in the cloud should be better for me as well and I keep thinking I should do this.

Of course paying someone assumes they will do their job. There are always incompetent companies out there to take your money.

Re: ZFS 2.3 released with ZFS raidz expansion

#184

Post by ryao »

crote wrote: post #146
chungy wrote: post #51

Earlier quoted context omitted.

I'm not sure that's really a caveat, it just means old data might be in an inoptimal layout. Even with that, you still get the full benefits of raidzN, where up to N disks can completely fail and the pool will remain functional.

I think it's a huge caveat, because it makes upgrades a lot less efficient than you'd expect. For example, home users generally don't want to buy all of their storage up front. They want to add additional disks as the array fills up. Being able to start with a 2-disk raidz1 and later upgrade that to a 3-disk and eventually 4-disk array is amazing. It's a lot less amazing if you end up with a 55% storage efficiency ra…

You have a couple options:

1. Delete the snapshots and rewrite the files in place like how people do when they want to rebalance a pool.

2. Use send/receive inside the pool.

Either one will make the data use the new layout. They both carry the caveat that reflinks will not survive the operation, such that if you used reflinks to deduplicate storage, you will find the deduplication effect is gone afterward.

Re: ZFS 2.3 released with ZFS raidz expansion

#185

Post by wkat4242 »

bolognafairy wrote: post #111
BSDobelix wrote: post #108

Earlier quoted context omitted.

>ZFS on OS X was killed because of Oracle licensing drama. Naa it was Jobs ego not the license: >>Only one person at Steve Jobs' company announces new products: Steve Jobs. https://arstechnica.com/gadgets/2016/06/zfs-the-other-new-ap...

It’s a cute story that plays into the same old assertions about Steve Jobs, but the conclusion is mostly baseless. There are many other, more credible, less conspiratorial, possible explanations.

It could have played into it though, but I agree the support contract that couldn't be worked out mentioned elsewhere in the thread is more likely.

But I think these things are usually a combination. When a business relationship sours, agreements are suddenly much harder to work out. The negotiators are still people and they have feelings that will affect their decisionmaking.

Re: ZFS 2.3 released with ZFS raidz expansion

#186

Post by harshreality »

Jnr wrote: post #135
nabla9 wrote: post #124

Earlier quoted context omitted.

License is not a real issue. It must be just distributed in separate module. No big hurdle.

From my point of view it is a real usability issue. zfs modules are not in the official repos. You either have to compile it on each machine or use unofficial repos, which is not exactly ideal and can break things if those repos are not up to date. And I guess it also needs some additional steps for secureboot setup on some distros? I really want to try zfs because btrfs has some issues with RAID5 and RAID6 (it is no…

Why are you considering raid5/6? Are you considering building a large storage array? If the data will fit comfortably (50-60% utilization) on one drive, all you need is raid1. Btrfs is fine for raid1 (raid1c3 for extra redundancy); it might have hidden bugs, but no filesystem is immune from those; zfs had a data loss bug (it was rare, but it happened) a year ago.

Why use zfs for a boot partition? Unless you're using every disk mounting point and nvme slot for a single large raid array, you can use a cheap 512GB nvme drive or old spare 2.5" ssd for the boot volume. Or two, in btrfs raid1 if you absolutely must... but do you even need redundancy or datasum (which can hurt performance) to protect OS files? Do you really care if static package files get corrupted? Those are easily reinstalled, and modern quality brand SSDs are quite reliable.

Re: ZFS 2.3 released with ZFS raidz expansion

#187

Post by klauserc »

endorphine wrote: post #25

Can someone describe why they would use ZFS (or similar) for home usage?

I use it on my work laptop. Reasons:

- a single solution that covers the entire storage domain (I don't have to learn multiple layers, like logical volume manager vs. ext4 vs. physical partitions) - cheap/free snapshots. I have been glad to have been able to revert individual files or entire file systems to an earlier state. E.g., create a snapshot before doing a major distro update. - easy to configure/well documented

Like others have said, at this point I would need a good reason, NOT to use ZFS on a system.

Re: ZFS 2.3 released with ZFS raidz expansion

#188

Post by wkat4242 »

kwanbix wrote: post #64
poisonborz wrote: post #59

I just don't get it how the Windows world - by far the largest PC platform per userbase - still doesn't have any answer to ZFS. Microsoft had WinFS and then ReFS but it's on the backburner and while there is active development (Win11 ships some bits time to time) release is nowhere in sight. There are some lone warriors trying the giant task of creating a ZFS compatibility layer with some projects, but they are far f…

Honest question. As an end user that uses Windows and Linux and does not uses ZFS, what I am missing?

Snapshots (Note: NTFS does have this in the way of Volume Shadow Copy but it's not as easily accessible as a feature to the end user as it is in ZFS). Copy on Write for reliability under crashes. Block checksumming for data protection (bitrot)

Re: ZFS 2.3 released with ZFS raidz expansion

#189

Post by wkat4242 »

badgersnake wrote: post #66
poisonborz wrote: post #59

I just don't get it how the Windows world - by far the largest PC platform per userbase - still doesn't have any answer to ZFS. Microsoft had WinFS and then ReFS but it's on the backburner and while there is active development (Win11 ships some bits time to time) release is nowhere in sight. There are some lone warriors trying the giant task of creating a ZFS compatibility layer with some projects, but they are far f…

NTFS is good enough for most people, who have a laptop with one SSD in it.

The benefits of ZFS don't need multiple drives to be useful. I'm running ZFS on root for years now and snapshots have saved my bacon several times. Also with block checksums you can at least detect bitrot. And COW is always useful.

Re: ZFS 2.3 released with ZFS raidz expansion

#190

Post by klauserc »

senectus1 wrote: post #24

Would love to use ZFS, but unfortunately Fedora just cant keep up with it...

I've been running Fedora on top of the excellent ZFSBootMenu[1] for about a year. You need to pay attention to the kernel versions supported by OpenZFS and might have to wait for support for a couple of weeks. The setup works fine otherwise.

[1] https://docs.zfsbootmenu.org

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