Re: Change in default vm_dirty_ratio

Arjan van de Ven
2007-06-19T00:12:59Z

> Is it good to keep tons of dirty stuff around? Sure. It allows overwriting
> (and thus avoiding doing the write in the first place), but it also allows
> for a more aggressive IO scheduling, in that you have more writes that you
> can schedule.

it also allows for an elevator that can merge more so that there are
less seeks...

so it's not all pure artificial ;(

I really don't like doing just-for-benchmark tuning ... but I wonder how
much real workloads this will get too (like installing or upgrading a
bunch of rpms)

As for the smoother IO thing.. there's already a kernel process that
writes this lot out after 5 seconds... so that ought to smooth some of
this out already.... I would hope.

(I'm not arguing this change is wrong, I'm just grinding my teeth on how
long updating rpms already takes... for no apparent reason)