Re: When will ZFS become stable?

On Fri, Jan 04, 2008 at 06:58:32PM +0100, Ivan Voras wrote:
> On 04/01/2008, Brooks Davis <brooks_at_freebsd.org> wrote:
> > On Fri, Jan 04, 2008 at 12:42:28PM +0100, Ivan Voras wrote:
> > > Hi,
> > >
> > > As far as I know about the details of implementation and what would it
> > > take to fix the problems, is it safe to assume ZFS will never become
> > > stable during 7.x lifetime?
> >
> > I suppose that depends what you mean by stable.
> 
> My yardstick is currently "when a month goes by without anyone
> complaining it crashed on him" :)

I'm not sure any file system we support meets that criteria...

> >It seems stable enough
> > for a number of applications today.
> 
> This number is not so large. It seems to be easily crashed by rsync,
> for example (speaking from my own experience, and also some of my
> colleagues).

I saw those crashes early one, but that's 90% of what the mirror server
I'm running does and I'm not seeing them any more.  I won't argue
everything is fixed, but ZFS seems much more stable than it was.

> > It's possible some of
> > the issues of memory requirements won't be fixable in 7.x, but I don't
> > think that's a given.
> 
> I listened to some of Pawel's talks and devsummit brainstormings and I
> get the feeling *none* of the problems can be fixed in 7.x, especially
> on i386. I'm just asking for more official confirmation.

My understanding is that ZFS will never be a great choice on any 32-bit
architecture without major changes Sun probably isn't interested in
making.  I think many of the problems people are reporting stem from
that.

> This is not a trivial question, since it involves deploying systems to
> be maintained some years into the future - if ZFS will become stable
> relatively shortly, it might be worth putting up with crashes, but if
> not, there will be no near-future deployments of it.

I don't think anyone is naive enough to say everything will be perfect
by any given date.  Reality doesn't work that way.  People looking to
deploy ZFS now will need to tolerate a certain amount of risk since it's
never been part of a FreeBSD release (and it's still quite new even in
Solaris).  Issues being unfixable in 7.x are one of those risks, but
that's always the case.

-- Brooks