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Comment by Fnoord | Hacker News Reader

Agreed, horrible idea for the time being, but you made it seem as if ZFS could run on these low resource systems.

There are certain features in ZFS which I'd love to run on embedded devices. I even remember Apple toying around with porting ZFS to macOS (back then called OSX or OS X) [1]. We're 10 years later, and only now has Apple rolled out APFS which has CoW and data integrity (yet no TimeMachine support for APFS).

EDIT: to those who commented, was it ECC RAM?

[1] https://en.wikipedia.org/wiki/ZFS#macOS_2

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My first ZFS install (almost 10 years ago) was on 512MB of RAM, sometimes including a Gnome 2 desktop. People get the RAM requirement thing out of proportion - yes it helps, because it's caching, and caching helps - and ZFS is a little bit heavier on metadata than other file systems (chiefly because of the checksums), but a lot of the online advice is IMO overly cautious, probably because you're giving advice to some random person on the internet and you have no real idea about how to characterize the workload that their storage system will be exposed to, and probably neither do they.

> Agreed, horrible idea for the time being, but you made it seem as if ZFS could run on these low resource systems.

I've installed ZFS on a machine with only 1GB of ram. Yea that's a lot for an embedded device, But it's not a lot of RAM in the grand scheme of things. Was it fast, no, but it definitely worked.

Exactly. But it does work. I’m being down voted by the clueless brigade.

Maybe not all because of your points, but rather that HN is allergic to a preachy attitude. Try to stay objective while humble and it will work better.

As the other commenter stated, the downvotes are most likely due to the holier than though attitude. It’s ok to be passionate and knowledgeable, but nobody wants to deal with jerks.

When we talk about relatively small amounts of RAM its not telling a lot how much RAM the device has but rather how much RAM is devoted to ZFS. Because an Android device on 1 GB RAM is a completely different beast than a FreeNAS devoted to serving files running 1 GB RAM. The same is true for 512 MB, 2 GB, etc.

PS: And was it ECC RAM?

> PS: And was it ECC RAM?

This myth seriously needs to die. ZFS does not care one whit what kind of RAM you use, any more than my other type of filesystem does.

Who puts ECC RAM in a small, low-power, embedded-style system like an RPi? It makes no sense.

It makes sense to this degree only, if you DONT use ECC no matter where you are using ZFS you are introducing potential checksum errors in the data path. ECC is not that much more than normal ram. To me it makes no sense to run ZFS even if in some tiny home NAS and leave the data path vulnerable to corruption of any kind. Why bother with ZFS at all if you don’t want complete protection? That’s just bizarre.

This, same reason i don't understand why scaleway don't use ECC RAM on production servers.

It's that important, I've seen corrupt RAM write bad data too many times and I don't even have thousands of servers...

No it’s not. I might want instant rollback on large databases on a development machine. Others might want transparent compression and send/receive on a small device. Neither has anything to do with “complete protection” yet both are easy to accomplish with ZFS.

There are a whole slew of reasons to run ZFS outside of mass redundant storage with “complete protection.” The decision to use ECC or not has nothing to do with ZFS. You may as well ask someone who is building an ext4 file server machine whether they “used ECC RAM”; it’s just as relevant.

Yet no one does that for EXT4 and they do it all the time for ZFS, because of one stupid post on the FreeNAS forums that has been roundly debunked a half-dozen times.

> Who puts ECC RAM in a small, low-power, embedded-style system like an RPi? It makes no sense.

Well, you can't put it in a RPi or smartphone or Synology if it isn't there in the first place because its soldered.

But if you build yourself a FreeNAS DIY or if you buy big iron for your company then why not.

You still get other benefits from something like ZFS w/o ECC RAM though (imagine CoW; useful on pretty much any computer), but with less certainty.

Without ECC, you get no less certainty than any other filesystem. It should not factor into discussions of when it is appropriate to use ZFS vs another filesystem.

Less certainty than if you'd have ECC RAM. If you can afford it, and you're using ZFS, you should seriously consider ECC RAM.

You aren’t getting my point. “If you can afford it, you should seriously consider ECC RAM” is the proper advice. ZFS has nothing to do with it.

No, he didn't. Not to me.

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