Re: [PATCH -mm] vmscan: make mapped executable pages the first class citizen

KOSAKI Motohiro
2009-05-12T03:01:12Z

> side effects
> ------------
>
> This patch is safe in general, it restores the pre-2.6.28 mmap() behavior
> but in a much smaller and well targeted scope.
>
> One may worry about some one to abuse the PROT_EXEC heuristic. But as
> Andrew Morton stated, there are other tricks to getting that sort of boost.
>
> Another concern is the PROT_EXEC mapped pages growing large in rare cases,
> and therefore hurting reclaim efficiency. But a sane application targeted for
> large audience will never use PROT_EXEC for data mappings. If some home made
> application tries to abuse that bit, it shall be aware of the consequences,
> which won't be disastrous even in the worst case.

ok, I lose.
if you can post good mesurement result, I'll ack this.