HAMMER2 VS XFS ( redhat ).

eranb

Hello,

I want to ask why should someone will want to use HAMMER2 and not centos - XFS ?
I can't find a discussion on this.

XFS is very old but redhat uses it on production .
Hammer2 is modern file system but not used on production.

Will hammer2 make sure the files written to disk with no data corruption ?

Do I need ECC memory when using hammer2 ?

Thanks.

netneo

eranb Do I need ECC memory when using hammer2 ?

I don't think so, no. I've had Dragonfly with HAMMER2 on one of my Thinkpads at one point and I don't have ECC.

If you're on Linux, you can check whether ECC is present in a number of ways:

How to check ECC RAM functionality
How to check if RAM is running in ECC mode

JuvenalUrbino

eranb Hammer2 is modern file system but not used on production.

because nobody is brave enough to assume a niche research project developed by a limited number of volunteers, , mostly untested outside of the development team, with no influential sponsors and no serious company commercializing it, to be production-ready and take it for granted

eranb Do I need ECC memory when using hammer2 ?

Not at all 😉

netneo

I've tried Dragonfly BSD a couple of times but my experience is very limited so I don't have an answer.

If you're going to use Dragonfly, I'd say just try it with HAMMER2 and see how it compares. All of this depends on your use case. It looks solid enough to me but as far as I know, there's no support for it on any other operating system.

Myself I use XFS all the time for my data and backups and the XFS utilities have proved to be very helpful. Elsewhere I use ext4 (e.g. on a Linux root partition) or FFS2 on *BSD.

Here are a few links that may be useful:

Dragonfly BSD on HAMMER
Dragonfly BSD on recovering data with HAMMER
Dragonfly BSD HAMMER Slider utility
FreeBSD forum on ZFS vs HAMMER (v. 1)
ComputingForGeeks.com - ext4 vs XFS comparison
Phoronix - A Look At The HAMMER2 File-System Performance With DragonFlyBSD 5.2
Phoronix - HAMMER2 Is Looking & Performing Good As The Future DragonFlyBSD File-System

That said, maybe you can address this question to the DflyBSD folks directly to find out how HAMMER2 compares to XFS. I'd be interested in finding out, too.

Cheers.

JuvenalUrbino

Comparing XFS and HAMMER2 doesn't make much sense IMHO, as HAMMER2 belongs to an entirely different generation of CoW filesystems -started by Sun with ZFS- which bring the very concept of FS to a further level, by adding a whole set of cool features. It would be much more interesting to write down a comparison chart between HAMMER2, ZFS, APFS, Btrfs and ReFS.
XFS may be better compared with VxFS, FFSv2, ext4...

XFS is a rock solid filesystem and aged really well (born on Sgi IRIX in the far '93), but I suspect Red Hat still resolving to XFS+LVM to be no more than a fallback choice in lack of proper replacement (Btrfs not being the one and ZFS held back from being redistributed/commercialized in a Linux distribution due to copyleft license incompatibilities)

bsduck

An obstacle to wider adoption is the fact it's DragonFly-specific.

If you want to use ZFS you can pick your OS between Solaris, FreeBSD, NetBSD, as well as various Linux and Illumos distributions. Most people will be fine with one of them.

XFS, ext4, Btrfs are Linux-specific, but Linux is widely used, has first class hardware support, and comes in lots of different distributions of all kinds, one of which can probably suit your needs.

To use HAMMER you need to run DragonFly, which is not widely used at all and comes with significant drawbacks for production use:

limited hardware support compared to more mainstream OS
no binary updates (rebuilding from source is required)
no long term support (only the latest release is supported)
lacking documentation

eranb

Thanks for the replies.

Another question :

Does ECC memory means that the files on disk are safer against data corruption ?

Why do I need ECC memory for ? will it keep my data on disk more safe ?

Thanks.

rvp

eranb Why do I need ECC memory for?

It's to... protect yo bits
from Cosmic Nits

So yo PeeCee
can rest easy.

(Don't need no fits
In ma bits!)

Is why you buy ECC
Memoreeee...