On 1/25/07, Vaidyanathan Srinivasan <[EMAIL PROTECTED]> wrote:
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.
I agree, we shouldn't take mmapped page into account. But Vaidy - even with your patch, we are still using the existing reclaimer, that means we dont ensure that only page cache is reclaimed/limited. mapped pages will be hit also. I think we still need to add a new scancontrol field to lock mmaped pages and remove unmapped pagecache pages only. -Aubrey - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/