Christoph Lameter wrote:
> On Wed, 24 Jan 2007, Vaidyanathan Srinivasan wrote:
>
>> With your patch, MMAP of a file that will cross the pagecache limit hangs the
>> system. As I mentioned in my previous mail, without subtracting the
>> NR_FILE_MAPPED, the reclaim will infinitely try and fail.
>
> Well mapped pages are still pagecache pages.
>
Yes, but they can be classified under a process RSS pages. Whether it
is an anon page or shared mem or mmap of pagecache, it would show up
under RSS. Those pages can be limited by RSS limiter similar to the
one we are discussing in pagecache limiter. In my opinion, once a
file page is mapped by the process, then it should be treated at par
with anon pages. Application programs generally do not mmap a file
page if the reuse for the content is very low.