First of all, I would like to thank Bob, Richard and Tim for
at least taking time to look at this proposal and responding ;)

It is also encouraging to see that 2 of 3 responders consider
this idea at least worth pondering and discussng, as it appeals
to their direct interest. Even Richard was not dismissive of it ;)

Finally, as Tim was right to note, I am not a kernel developer
(and won't become one as good as those present on this list).
Of course, I could "pull the blanket onto my side" and say
that I'd try to write that code myself... but it would
probably be a long wait, like that for "BP rewrite" - because,
I already have quite a few commitments and responsibilities
as an admin and recently as a parent (yay!)

So, I guess, my piece of the pie is currently limited to RFEs
and bug reports... and working in IT for a software development
company, I believe (or hope) that's not a useless part of the
process ;)

I do believe that ZFS technology is amazing - despite some
shortcomings that are still present - and I do want to see
it flourish... ASAP! :^)


2012-01-08 7:15, Tim Cook wrote:

On Sat, Jan 7, 2012 at 7:37 PM, Richard Elling <
<>> wrote:

    Hi Jim,

    On Jan 6, 2012, at 3:33 PM, Jim Klimov wrote:

     > Hello all,
     > I have a new idea up for discussion.

I disagree.  Dedicated spares impact far more than availability.  During
a rebuild performance is, in general, abysmal.  ...
  If I can't use the system due to performance being a fraction of what
it is during normal production, it might as well be an outage.

     > I don't think I've seen such idea proposed for ZFS, and
     > I do wonder if it is at all possible with variable-width
     > stripes? Although if the disk is sliced in 200 metaslabs
     > or so, implementing a spread-spare is a no-brainer as well.

    Put some thoughts down on paper and work through the math. If it all
    out, let's implement it!
      -- richard

I realize it's not intentional Richard, but that response is more than a
bit condescending.  If he could just put it down on paper and code
something up, I strongly doubt he would be posting his thoughts here.
  He would be posting results.  The intention of his post, as far as I
can tell, is to perhaps inspire someone who CAN just write down the math
and write up the code to do so.  Or at least to have them review his
thoughts and give him a dev's perspective on how viable bringing
something like this to ZFS is.  I fear responses like "the code is
there, figure it out" makes the *aris community no better than the linux

     > What do you think - can and should such ideas find their
     > way into ZFS? Or why not? Perhaps from theoretical or
     > real-life experience with such storage approaches?
     > //Jim Klimov

As always, feel free to tell me why my rant is completely off base ;)


zfs-discuss mailing list

Reply via email to