Re: [rfc] [patch] mm: zone_reclaim fix for pseudo file systems

Andrew Morton
2007-07-31T04:47:56Z

On Mon, 30 Jul 2007 19:36:04 -0700 (PDT) Christoph Lameter <clameter@sgi.com> wrote:

> On Mon, 30 Jul 2007, Andrew Morton wrote:
>
> > That makes sense, but any fix we do here won't fix things for regular
> > reclaim.
>
> Standard reclaim has the same issues. It uselessly keeps
> scanning the unreclaimable file backed pages.

Well it shouldn't. That's what all_unreclaimable is for. And it does
work. Or used to, five years ago. Stuff like this has a habit of breaking
because we don't have a test suite.

> Fixing this will also
> enhance regular reclaim.
>
> > - account file-backed pages, BDI_CAP_NO_ACCT_DIRTY pages and
> > BDI_CAP_NO_WRITEBACK separately. ie: zone accounting pretty
> > much follows the BDI_CAP_ selectors.
>
> Or BDI_CAP_UNRECLAIMABLE....

Yeah, that's nice and direct.