On 2018-07-21 01:26, my123 (@never_released) wrote:
Hi,
It's worth noting that the cheaper Pentium parts support ECC such as
the Pentium G4560.
Yeah, I know. I got the i3 kinda cheap, that's why I bought it.
Personally, I believe that the ZFS scrub story is a bit overblown for
non-ECC systems, never had an issue with it.
I agree with this, and the "myth" that ZFS RaidZ1 ain't safe and you
should use RaidZ2 or higher.
There's some paranoia running wild in the FreeNAS community.
On 21/07/2018 00:12, Jasse Jansson wrote:
On 2018-07-20 23:12, Xin LI wrote:
On Fri, Jul 20, 2018 at 2:07 PM Rickard von Essen
<[email protected]> wrote:
Both "scrub of death" and "you have to use ECC ram when you use
ZFS" are myths.
+1. ECC is not a requirement for ZFS, and ZFS only rewrites data when
it sees checksum mismatch AND the replica were correct, so the chance
of scrub damaging data is extremely low because you need at least two
flipped bits in the first place.
You do want to use ECC RAM if the data is valuable though; the small
price difference will definitely worth it if you ever see a corruption
that you can't recover from.
In my experience "I" am the biggest threath to my stored pics and
other stuff I stored in my servers in my basement.
I have accidently countersunk an external HD used for backups twice
in the last 10 years, and I doubt I'll have ever been so close to a
lethal heart attac, twice again.
Both times all the files could be restored using a data recovery
program I can't remember the name of right now.
I don't take that risk anymore.
My main server runs FreeNAS with a 5-disk raidZ volume (ECC RAM),
scrubbed twice every month.
My backup server also runs FreeNAS with a 5-disk RaidZ volume (ECC
RAM), also scrubbed twice every month.
Both servers are attached to UPS power.
The backup server rsynch's the whole volume every third night.
I log in regularly to my servers to check they are OK.
I also make sure to replace the HD's every 3 years.
You really think I would risk another near death experience by
running NON-ECC RAM for the little price difference there is today.
But it's your pics/data/files and your choice.
Oh, btw, if you are going to buils a new server with ECC memory, make
sure the CPU supports it, the latest i3's don't.
One good discussion on the topic can be found on:
https://reddit.app.link/QOrzkoipIO
On Fri, Jul 20, 2018, 22:37 Predrag Punosevac
<[email protected]> wrote:
Hi,
I was wondering if Matt and the other developers involved can shed
some
light onto the future of HAMMER1 and ultimately of DragonFly.
I started dicking with DragonFlyBSD 7-8 years ago mostly due to my
curiosity about HAMMER. I tried few times in the past to use DF as a
main file server at the place of my employment just quickly to
reverse
back to ZFS and FreeBSD but my home file server is still happily
running
dfly# uname -a
DragonFly dfly.bagdala2.net 5.2-RELEASE DragonFly v5.2.2-RELEASE #17:
dfly# mount
ROOT on / (hammer, noatime, local)
devfs on /dev (devfs, nosymfollow, local)
/dev/serno/B620550018.s1a on /boot (ufs, local)
/pfs/@@-1:00001 on /var (null, local)
/pfs/@@-1:00002 on /tmp (null, local)
/pfs/@@-1:00003 on /home (null, local)
/pfs/@@-1:00004 on /usr/obj (null, local)
/pfs/@@-1:00005 on /var/crash (null, local)
/pfs/@@-1:00006 on /var/tmp (null, local)
procfs on /proc (procfs, local)
DATA on /data (hammer, read-only, noatime, local)
BACKUP on /backup (hammer, noatime, local)
/dev/serno/5QG00XF0.s1e@DATA on /test-hammer2 (hammer2, local)
/data/pfs/@@-1:00001 on /data/backups (null, local)
/data/pfs/@@-1:00002 on /data/nfs (null, NFS exported, local)
I feel the time to physically rebuild my home file server slowly
approaching so I would like to be ready for that day.
In the light of the fact that HAMMER2 is out and recommended for root
partition does HAMMER have any future? I see Tomohiro Kusumi still
having a commit or two a month which touches HAMMER but it seems that
even his commits are minor bug fixes related to his work/poking with
HAMMER2. Is everyone else done playing with HAMMER1?
Is HAMMER2 now stable enough to guarantee consistency of my data? My
concern is that it typically takes at least 10 years for a file
system
to mature under lot of use and abuse by a much wider community
than DF.
BTRFS is vaporware even after major investment since 2007. With
the size
of the DF community I feel it might takes 20-30 years for HAMMER2
to be
trully safe.
One of the main advantages for me personally of HAMMER1 over ZFS
besides
fine grained history was that it seems to be ok-ish with non-ECC RAM.
Scrub of death
https://forums.freenas.org/index.php?threads/ecc-vs-non-ecc-ram-and-zfs.15449/
is real thing and I feel very uncomfortable using ZFS on my cheap
home
hardware. I know that under non-budgetary constrains I should use ECC
memory with DF as well. How safe HAMMER2 is with non-ECC memory?
Cheers,
Predrag
