gmirror & sparc64 oddness

[Pawel Jakub Dawidek]

On Tue, Apr 12, 2005 at 08:12:32AM +0100, Chris Elsworth wrote:
+> On Mon, Apr 11, 2005 at 03:57:37PM +0200, Pawel Jakub Dawidek wrote:
+> > 
+> > No, the problem is that geom_sunlabel class operates only on rank#1
+> > providers (disks, etc.).
+> > Mirrors are not rank#1 of course, because there are providers under them.
+> > This was done to prevent recursive labels creations.
+> > 
+> > geom_bsd and geom_mbr are already fixed and are using MD5 to verify
+> > if metadata were already used for slices/labels creation.
+> > 
+> > I don't have HW to test this, but please try this patch and tell me
+> > if it works for you:
+> 
+> Hello Pawel,
+> 
+> This seems to work fine - no problems so far and it's happily booted
+> off a gmirror device. The only thing I've noticed so far is that
+> writes during a synchronization of components don't seem to be
+> appearing in gstat for the mirror:
+> 
+> dT: 1.010  flag_I 1000000us  sizeof 288  i -1
+>  L(q)  ops/s    r/s   kBps   ms/r    w/s   kBps   ms/w   %busy Name
+>     0      0      0      0    0.0      0      0    0.0    0.0| acd0
+>     1     77      0      0    0.0     77   9757    6.6   50.9| da0
+>     0     77     77   9884    1.8      0      0    0.0   13.8| da1
+>     0     77     77   9884    1.8      0      0    0.0   14.1| mirror/gm0
+> 
+> This is a sync from da1 to da0, but notice how the writes values for
+> the mirror are zero. I can't recall offhand whether this happens on
+> i386 as well, but I just thought I'd point it out as an oddity ; or
+> this is recognised behaviour?

It's perfect normal - I read from the mirror, but write goes only to
da0 provider, so you can see writes to da0 and read from da1 and gm0.

+> Thanks very much for the patch, hope it makes it into the tree :)

Yes, thanks for testing.

-- 
Pawel Jakub Dawidek                       http://www.wheel.pl
pjd at FreeBSD.org                           http://www.FreeBSD.org
FreeBSD committer                         Am I Evil? Yes, I Am!
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-geom/attachments/20050412/d8945033/attachment.bin