[dm-devel] [PATCH v3] multipath-tools: intermittent IO error accounting to improve reliability

[Martin Wilck]

On Tue, 2017-09-05 at 10:59 +0800, Guan Junxiong wrote:
> Hi Martin,
> Thanks for you remarks and compiling check.
> An new patch will be updated in this week.
> Other response is inline.
> 
> Cheers
> Guan Junxiong
> 
> On 2017/9/5 4:59, Martin Wilck wrote:
> >  map_discovery (struct vectors * vecs)
> > >  {
> > >  	struct multipath * mpp;
> > > @@ -1134,6 +1170,7 @@ uev_trigger (struct uevent * uev, void *
> > > trigger_data)
> > >  	if (!strncmp(uev->kernel, "dm-", 3)) {
> > >  		if (!strncmp(uev->action, "change", 6)) {
> > >  			r = uev_add_map(uev, vecs);
> > > +			uev_pathfail_check(uev, vecs);
> > >  			goto out;
> > >  		}
> > >  		if (!strncmp(uev->action, "remove", 6)) {
> > 
> > It's interesting that you have chosen to act on kernel PATH_FAILED
> > events here. The existing multipath-tools code doesn't do that, it
> > relies on its internal state information (pathinfo, checkers)
> > instead.
> > I am not saying that what you're doing is wrong, but it deserves
> > some
> > explanation. 
> > 
> > Regards
> > Martin
> > 
> 
> the kernel PATH_FAILED events will only be issued when path IO error
> occours.

Are you positive about that? I thought I could swear that've seen those
for path deletion.

I need to double-check.

Martin


-- 
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