Re: ext3 fsync being starved for a long time by cp and cronjob

On Friday 25 August 2006 14:34, Jens Axboe wrote:
> On Fri, Aug 25 2006, Andi Kleen wrote:
> > On Friday 25 August 2006 14:26, Jens Axboe wrote:
> > > On Fri, Aug 25 2006, Andi Kleen wrote:
> > > > 
> > > > > Does deadline do better?
> > > > 
> > > > It's not really repeatable workload. It's just my workstation which
> > > > got into this unpleasant state while me trying to get work done.
> > > > 
> > > > I can change it to deadline and see if I see this still again, but it might
> > > > take some time.
> > > 
> > > Yeah, a test case might be simpler to write and test with. I'll see if I
> > > can come up with something.
> > 
> > So you think it's the elevator? I was about to blame JBD.
> 
> Not sure, it might be ext3. Hence the deadline test would be useful. All
> I know for sure is that the io scheduling for fsync() can be improved.
> Did you try data=writeback?

No. And I would prefer to not try that because I would have to run
my workstation with it for a long time, and ordered seems somewhat
safer for that.

-Andi

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