On Mon, May 12, 2014 at 7:36 AM, Andi Kleen <andi@xxxxxxxxxxxxxx> wrote: > Armin Rigo <arigo@xxxxxxxxx> writes: > >> Here is a note from the PyPy project (mentioned earlier in this >> thread, and at https://lwn.net/Articles/587923/ ). > > Your use is completely bogus. remap_file_pages() pins everything > and disables any swapping for the area. Wait, what's wrong with swapping pages from non-linear vmas? try_to_umap() can handle them, though not very effectively. Some time ago I was thinking about tracking rmap for non-linear vmas, something like second-level tree of sub-vmas stored in non-linear vma. This could be done using exising vm_area_struct, and in rmap tree everything will looks just as normal. We'll waste some kernel memory, but it also will remove complexity from rmap and make non-linear vmas usable for all filesystems not just for shmem. But it's not worth. I ACK killing it. Maybe we should keep flag on vma and hide/merge them in proc/maps. Bloating files/dirs in proc might be bigger problem than non-existent performance regression. > > -Andi > -- > ak@xxxxxxxxxxxxxxx -- Speaking for myself only > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@xxxxxxxxx. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>