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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

#41

Post by j1elo »

imiric wrote: post #37
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!

Simplicity. There's a lot of complexity in ZFS I'd rather not depend on, and because it does so many things it's a big investment and liability to switch to. While I understand why it would be useful in a corporate setting, for personal use I've found the combination of LUKS+LVM+SnapRAID to work well and don't see the benefit of switching to ZFS. Two of those are core Linux features, and SnapRAID has been rock solid,…

What about if you were just starting today, with 0 knowledge about basically anything related to storage and how to do it right?

That's my case, I'm learning before setting up a cheap home lab and a NAS, and I'm wondering if biting into ZFS is just the best option that I have given today's ecosystem.

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

#42

Post by mnd999 »

ghaff wrote: post #10
jbverschoor wrote: post #3

Earlier quoted context omitted.

Licensing. Similarly, otherwise it would've been included in macOS a long time ago (as the default fs according to some..)

And it's arguably even a bigger issue on Linux distros.

It’s a moderate pain on Linux and then only really that if you’re running on something bleeding-edge like Arch. Otherwise it’s just a kernel module like any other.

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

#44

Post by simcop2387 »

livueta wrote: post #39
colechristensen wrote: post #21

Earlier quoted context omitted.

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…

> Enable lz4 compression everywhere Is the perf penalty low enough now that it just doesn't matter? I've always disabled compression on datasets I know are going to store only high-entropy data, like encoded video, that has a poor compression ratio. I second the hot spare recommendation many times over. It can save your bacon.

It's generally the other way around actually, aside from storing already highly compressed datasets (e.g. video). The compression from lz4 will get you better effective performance because of the lower amount of io that has to be done, both in throughput and latency on zfs. This is because your CPU can usually do lz4 at hundreds of gb/s compared to the dozen you might get on your spinning rust disks.

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

#45

Post by eptcyka »

Dylan16807 wrote: post #31
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!

> why anyone uses BTRFs (UnRaid or any other form of software raid that isn't ZFS) is still beyond me. BTRFS can do after-the-fact deduplication (with much better performance than ZFS dedup) and copy-on-write files. And you can turn snapshots into editable file systems.

I've had 3 catastrophic BTRFS failures. In two cases, the root filesystem just ran out of space and there was no way to repair the partition. Last time, the partition was just rendered unmountable after a reboot. All data was lost.No such thing has ever happened with ZFS for me.

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

#46

Post by livueta »

simcop2387 wrote: post #44
livueta wrote: post #39

Earlier quoted context omitted.

> Enable lz4 compression everywhere Is the perf penalty low enough now that it just doesn't matter? I've always disabled compression on datasets I know are going to store only high-entropy data, like encoded video, that has a poor compression ratio. I second the hot spare recommendation many times over. It can save your bacon.

It's generally the other way around actually, aside from storing already highly compressed datasets (e.g. video). The compression from lz4 will get you better effective performance because of the lower amount of io that has to be done, both in throughput and latency on zfs. This is because your CPU can usually do lz4 at hundreds of gb/s compared to the dozen you might get on your spinning rust disks.

Neat! Makes sense.

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

#47

Post by Dylan16807 »

eptcyka wrote: post #45
Dylan16807 wrote: post #31

Earlier quoted context omitted.

> why anyone uses BTRFs (UnRaid or any other form of software raid that isn't ZFS) is still beyond me. BTRFS can do after-the-fact deduplication (with much better performance than ZFS dedup) and copy-on-write files. And you can turn snapshots into editable file systems.

I've had 3 catastrophic BTRFS failures. In two cases, the root filesystem just ran out of space and there was no way to repair the partition. Last time, the partition was just rendered unmountable after a reboot. All data was lost.No such thing has ever happened with ZFS for me.

I've had some annoying failures too. But I wasn't listing pros and cons, I was explaining that there are some very notable features that ZFS lacks.

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

#48

Post by ghaff »

mnd999 wrote: post #42
ghaff wrote: post #10

Earlier quoted context omitted.

And it's arguably even a bigger issue on Linux distros.

It’s a moderate pain on Linux and then only really that if you’re running on something bleeding-edge like Arch. Otherwise it’s just a kernel module like any other.

But it doesn't ship with either Red Hat or SUSE distros, which is an issue for supported commercial use.

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

#49

Post by atmosx »

gregmac wrote: post #30
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!

For my big media volume, which had existed for around 10 years, I use snapraid. Because of several things: * I can mix disk sizes * I can add new disks over time as needed * If something dies, up to the entire server, I can just stick any data disk in another system and read it I didn't want to become a zfs expert (and the learning curve seems steep!), and I didn't want to spend thousands of dollars on new gear (dedi…

The learning curve of ZFS compared to every alternative out there is significantly lower IMO. The interface is easier and the guides online are great.

There are drawbacks as the one discussed here, but as a Linux user who doesn’t want to mess up with the FS and uses ZFS for the backup server, the experience has been great so far.

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

#50

Post by dsr_ »

bearjaws wrote: post #19

Just upgraded my home NAS, had to swap all 8 drives, took 7 days... Not to mention it doubled the size of the array, I would have been much happier with an incremental increase.

With RAID10, one could swap out 2 drives to get a size increase.

With 2 4 disk vdevs, one could swap out 4 drives for a size increase.

So I'm assuming you have a single 8 disk vdev, and no spare places to put disks.

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