RE: [PATCHv24 00/16] Contiguous Memory Allocator

Marek Szyprowski
2012-04-11T06:48:33Z

Hi,

On Tuesday, April 10, 2012 7:20 PM Sandeep Patil wrote:

> >> This is (yet another) update of CMA patches.
> >
> >
> > How well CMA is supposed to work if you have mlocked processes? I've
> > been testing these patches, and noticed that by creating a small mlocked
> > process you start to get plenty of test_pages_isolated() failure warnings,
> > and bigger allocations will always fail.
>
> CMIIW, I think mlocked pages are never migrated. The reason is because
> __isolate_lru_pages() does not isolate Unevictable pages right now.
>
> Minchan added support to allow this but the patch was dropped.
>
> See the discussion at : https://lkml.org/lkml/2011/8/29/295

Right, we are aware of this limitation. We are working on solving it but we didn't
consider it a blocker for the core CMA patches. Such issues can be easily fixed with
the incremental patches.

Best regards
--
Marek Szyprowski
Samsung Poland R&D Center