From: Linus Torvalds Date: Tue, 30 Jan 2007 00:37:38 +0000 (-0800) Subject: Fix balance_dirty_page() calculations with CONFIG_HIGHMEM X-Git-Tag: v2.6.20-rc7~49 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dc6e29da9162fa8fa2a9e798569c0f6e87975614;p=pandora-kernel.git Fix balance_dirty_page() calculations with CONFIG_HIGHMEM This makes balance_dirty_page() always base its calculations on the amount of non-highmem memory in the machine, rather than try to base it on total memory and then falling back on non-highmem memory if the mapping it was writing wasn't highmem capable. This not only fixes a situation where two different writers can have wildly different notions about what is a "balanced" dirty state, but it also means that people with highmem machines don't run into an OOM situation when regular memory fills up with dirty pages. We used to try to handle the latter case by scaling down the dirty_ratio if the machine had a lot of highmem pages in page_writeback_init(), but it wasn't aggressive enough for some situations, and since basing the dirty ratio on highmem memory was broken in the first place, let's just stop doing so. (A variation of this theme fixed Justin Piszcz's OOM problem when copying an 18GB file on a RAID setup). Acked-by: Nick Piggin Cc: Justin Piszcz Cc: Andrew Morton Cc: Neil Brown Cc: Ingo Molnar Cc: Randy Dunlap Cc: Christoph Lameter Cc: Jens Axboe Cc: Peter Zijlstra Cc: Adrian Bunk Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed