On 11/04/17 18:44, Konstantin Olchanski wrote:
> On Tue, Apr 11, 2017 at 11:13:25AM +0200, David Sommerseth wrote:
>>
>> But that aside, according to [1], ZFS on Linux was considered stable in
>> 2013.  That is still fairly fresh, and my concerns regarding the time it
>> takes to truly stabilize file systems for production [2] still stands.
>>
> 
> Why do you worry about filesystem stability?
> 
> So what if it eats your data every 100 years due to a rare bug? You do have
> backups (filesystem stability does not protect you against
> fat-fingering the "rm" command), and you do archive your data, yes?
> You do have a hot-spare server (filesystem stability does not protect
> you against power supply fire) and you do have disaster mitigation plans
> (filesystem stability does not protect you against "server is down,
> you are fired!").
> 
> So what if it eats your data every 1 week due to a frequent bug? How is that
> different from faulty hardware eating your data? (like the cheap intel pcie ssd
> eating all data on xfs and ext4 within 10 seconds of booting). You build
> a system, you burn it in, you test it, if it works, it works, if it does not,
> you throw zfs (or the hardware) into the dumpster, start again with yfs, qfs, whatever.
> 
> How else can you build something that works reliably? Using only components annointed
> by the correct penguin can only take you so far.

It's called risk assessment and management.  You consider the risks, and
newer file systems have more bugs than older file systems.  Consider the
amount of users using ext4 and XFS, vs btrfs/zfs ... and in which of
these groups do you hear more about users experiencing data loss?

And I do care about data loss.  Because if that happens, I need to start
running restore jobs from backups and recover files and file systems.
So having a stable and rock solid file system reduces the chances of
extra work for me.  And my users are much more happy too.

Why do you think I'm running RAID 6?  To reduce the risk of data loss if
even 2 drives decides to bail out.  And if all that should explode, then
I have backups to restore.  And if the local backup fails, I have an
offsite backup as well.  Because data loss is really annoying for me and
my users.

But even with all that ... RAID 6 won't save me from a file system going
crazy and leaving data into the void.  So the stability and matureness
of the file system is equally important.

If you don't need to care for you data in 1-2 months ... then I
understand you being willing to use less stable and mature file systems.


-- 
kind regards,

David Sommerseth