Re: Btrs vs ext4. Which one is more reliable?

[Dan <ganchya@gmail.com>]

Dear Andy,

Thanks a lot for your answer.

On Sat, Jul 29, 2017 at 6:59 AM, Andy Smith <andy@strugglers.net> wrote:
> Hello,
>
> On Fri, Jul 28, 2017 at 04:27:32PM +0200, Dan wrote:
>> I have a NFS4 server with ext4. I'm moving to Debian Stretch. I wonder if I
>> should switch to Btrfs.
>
> I personally wouldn't. I do use btrfs at home and wish I didn't,
> will be moving away from it soon.
>

I'll follow your advice and continue using ext4. Too bad that btfrs is
still not ready. Looking forward to the time when Btrfs will be ready
for production.

>
> You could consider ZFS on Linux.
>
>     http://zfsonlinux.org/
>

I prefer to use something that is in the "official" linux kernel tree.
Too bad there are these licence issues (CDDL vs GPL)

>> My understanding is that the only thing that prevents silent corruption in
>> ext4 is the hard drive CRC (Cyclic Redundancy Check Error). Is that enough
>> for a server?
> Having RAID and scrubbing it regularly helps. It will at least spot
> mismatches. The mdadm package on Debian does that by default once
> per month and I could recommend making that more often if it doesn't
> cause you performance issues. Also note that if you only have a two
> way mirror and you find out there are mismatches, you may not be
> able to tell which mirror has the correct data. Forcing md to fix it
> will cause it to pick one side at random.

I'll take a look into the mdadm package and will consider RAID.

> The worst I've seen on the zfsonlinux list in the last couple of
> years is people reporting abnormally low performance in their
> configuration.

Hope that some day Oracle will free the license of ZFS and let the
Linux community use it under the GPL terms.

Best,
Daniel