Re: Undo aic7xxx changes (now rc7+aic20030603)

Willy Tarreau
2003-06-24T22:07:05Z

On Tue, Jun 24, 2003 at 11:26:09PM +0200, Stephan von Krawczynski wrote:

> sorry, you probably misunderstood my flaky explanation. What I meant was not a
> cached block from the _tape_ (obviously indeed a char-type device) but from the
> 3ware disk (i.e. the other side of the verification). Consider the tape
> completely working, but the disk data corrupt (possibly not from real reading
> but from corrupted cache).

Ah, OK ! I didn't understand this. You're right, this is also a possibility.
Perhaps a tar cf - /mnt/3ware | chkblk would get evidence of somme corruption ?

<...snip... OK for these points ...>

> Hm, interestingly the former freeze bug (solved by marcelo through backout of
> some patch in rc8) did not show up in UP. Since then I did not test UP any
> more. The problem itself does not necessarily point to flaky hardware, as I
> would have no idea how bad cache can only show up during a tape verification,
> that does not sound all that reasonable.

OK, I agree. And right after posting, I remembered that if this was the case,
you should also see some MCEs which doesn't seem to be your case.

> More likely could be a SMP race anywhere from nfs-server, 3ware disk driver to
> page cache, or not?

fairly possible. That's also what Justin suggested in the past, BTW :-)

Cheers,
Willy