Re: [PATCH 6/8] fs,xfs: Allow kswapd to writeback pages

Mel Gorman
2010-07-19T14:43:29Z

On Mon, Jul 19, 2010 at 10:20:51AM -0400, Christoph Hellwig wrote:
> On Mon, Jul 19, 2010 at 02:11:28PM +0100, Mel Gorman wrote:
> > As only kswapd and memcg are writing back pages, there should be no
> > danger of overflowing the stack. Allow the writing back of dirty pages
> > in xfs from the VM.
>
> As pointed out during the discussion on one of your previous post memcg
> does pose a huge risk of stack overflows.

I remember. This is partially to nudge the memcg people to see where
they currently stand with alleviating the problem.

> In the XFS tree we've already
> relaxed the check to allow writeback from kswapd, and until the memcg
> situation we'll need to keep that check.
>

If memcg remains a problem, I'll drop these two patches.

--
Mel Gorman
Part-time Phd Student Linux Technology Center
University of Limerick IBM Dublin Software Lab