Re: [HEADS UP] Merge of projects/gvinum to head

On tir, mar 17, 2009 at 09:52:31am -0300, Nenhum_de_Nos wrote:
> 
> On Tue, March 17, 2009 06:49, Ulf Lilleengen wrote:
> > On man, mar 16, 2009 at 11:07:12pm -0300, Nenhum_de_Nos wrote:
> >>
> >> On Mon, March 16, 2009 12:59, Ulf Lilleengen wrote:
> >> > On man, mar 16, 2009 at 04:58:00pm +0100, Ulf Lilleengen wrote:
> >> >> Hello,
> >> >>
> >> >> This is a heads-up for a merge of gvinum project code into HEAD. This
> >> >> means
> >> >> that gvinum implementation will be changed some. The code is based on
> >> >> the
> >> >> work done by Lukas Ertl as well as the work I did before/during
> >> Google
> >> >> SoC
> >> >> 2007 and afterwards. It has been staying in p4 for some time, and
> >> then
> >> >> moved
> >> >> to the subversion project repository not long ago. The main reason
> >> for
> >> >> the
> >> >> delay of getting this into HEAD have been the lack of reviewers of
> >> the
> >> >> code,
> >> >> but after some discussion and help from testers, I've decided this is
> >> a
> >> >> good
> >> >> time to get it in (should perhaps have been merged a bit earlier)
> >> >> Testers
> >> >> have spotted several differences from the original gvinum, and I've
> >> >> tried to
> >> >> make it behave as the old implementation wherever that seemed the
> >> best
> >> >> way to
> >> >> go. Luckily, the work has gotten a bit of attention lately, thanks to
> >> >> Rick C.
> >> >> Petty for helping out with testing and bugfixing, as well as all
> >> others
> >> >> who
> >> >> have dared to run the new gvinum. So, what does this update offer?
> >> >
> >> > And I plan on importing it within 1-2 weeks :)
> >>
> >> great work, thanks.
> >>
> >> what's the status of raid5 ? is it ok to production enviroments ? I have
> >> been using gmirror and gstripe just cause I can't do raid5 and I'm
> >> waiting
> >> for ZFS to hit production state.
> >>
> > I would say that since the raid5 code hasn't changed much in terms of
> > functionality, meaning that much of the code concerning raid5 is the same,
> > it
> > should provide at least the same production quality as gvinum in 7.x. What
> > are your experiences with gvinum raid5 in 7.x?
> 
> none, as I always read that the code was not ok or was not doing what
> raid5 is all about (those parity counts), I never was brave enough to try
> it. is this all wrong ?
> 
I've not heard of any issues with the actual raid5 algorithms to be wrong,
only gvinum being a bit to sensitive when doing administrative stuff like
switching disks etc. as it would crash if you didn't do things in the correct
order etc.  I've used it on a few storage servers without any problems
directly related to raid5.

-- 
Ulf Lilleengen