Re: More ext3 fileserver woes ...

[Andrew Morton <akpm zip com au>]

Neil Brown wrote:
> 
> On Wednesday June 5, akpm zip com au wrote:
> > Neil Brown wrote:
> > >
> > > ...
> > > But with ext3 I see different numbers.
> > >
> > > Jun  6 12:04:44 elfman kernel: buffer on 5 has age 9511
> > > Jun  6 12:04:44 elfman kernel: buffer on 5 has age 9512
> > > Jun  6 12:04:44 elfman kernel: buffer on 5 has age 9513
> >
> > ugh.
> >
> > I suppose this will fix?
> 
> Well... it certainly changes the symptom nicely:
> Jun  6 15:05:07 elfman kernel: buffer on 5 has age 498
> Jun  6 15:05:14 elfman kernel: buffer on 5 has age 492
> Jun  6 15:05:14 elfman kernel: buffer on 0 has age 420
> Jun  6 15:05:19 elfman kernel: buffer on 5 has age 496
> Jun  6 15:05:25 elfman kernel: buffer on 5 has age 499
> Jun  6 15:05:30 elfman kernel: buffer on 5 has age 493
> 
> which is suggestive that it fixes the problem....

yup.

> But how sure are you that it doesn't introduce another problem????

reasonably.

> It's not that I think it will (it looks quite believable to me), but
> I'm feeling rather fragile about my fileservers at the moment....
> 
> I'll probably try it out for real on Wednesday next week.
> 

OK.  I'll dig up a better fix soonish.  I assume we're running
set_buffer_flushtime() against buffers which are already on the
LRU. 

-