Re: Change in default vm_dirty_ratio

Nadia Derbey
2007-06-21T12:32:59Z

Dave Jones wrote:
> On Mon, Jun 18, 2007 at 04:47:11PM -0700, Andrew Morton wrote:
>
> > Frankly, I find it very depressing that the kernel defaults matter. These
> > things are trivially tunable and you'd think that after all these years,
> > distro initscripts would be establishing the settings, based upon expected
> > workload, amount of memory, number and bandwidth of attached devices, etc.
>
> "This is hard, lets make it someone else's problem" shouldn't ever be the
> answer, especially if the end result is that we become even more
> dependant on bits of userspace running before the system becomes useful.
>
> > Heck, there should even be userspace daemons which observe ongoing system
> > behaviour and which adaptively tune these things to the most appropriate
> > level.
> >
> > But nope, nothing.
>
> See the 'libtune' crack that people have been trying to get distros to
> adopt for a long time.
> If we need some form of adaptive behaviour, the kernel needs to be
> doing this monitoring/adapting, not some userspace daemon that may
> not get scheduled before its too late.
>

I'm wondering whether AKT I proposed a couple of months ago wouldn't be
more appropriate (provided that we find the perfect heuristics to tune
the dirty_ratio ;-) )
see thread http://lkml.org/lkml/2007/1/16/16

Regards,
Nadia