Re: Linux 2.4.5-ac15

[Mike Galbraith]

On Thu, 21 Jun 2001, Marcelo Tosatti wrote:

> On Thu, 21 Jun 2001, Mike Galbraith wrote:
>
> > On Thu, 21 Jun 2001, Marcelo Tosatti wrote:
> >
> > > >  2  4  2  77084   1524  18396  66904   0 1876   108  2220 2464 66079   198   1
> >                                                                    ^^^^^
> > > Ok, I suspect that GFP_BUFFER allocations are fucking up here (they can't
> > > block on IO, so they loop insanely).
> >
> > Why doesn't the VM hang the syncing of queued IO on these guys via
> > wait_event or such instead of trying to just let the allocation fail?
...
> > Does failing the allocation in fact accomplish more than what I'm
> > (uhoh:) assuming?
>
> No.

hmm..

Jun 18 07:11:36 kernel: reclaim_page: salvaged ref:1 age:0 buf:0 cnt:1
Jun 18 07:11:36 last message repeated 27 times

One thing that _could_ be done about looping allocations is to steal
a page from the clean list ignoring PageReferenced (if you have any).
That would be a very expensive 'rob Peter to pay Paul' trade though.

	-Mike