On Wed, Jul 07, 2010 at 04:37:10PM -0700, Andrew Morton wrote: > On Wed, 7 Jul 2010 19:16:11 -0400 > Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > > Currently there's three possible values we pass into the flusher thread > > for the nr_pages arguments: > > I assume you're referring to wakeup_flusher_threads(). In that context I refer to everything using the per-bdi flusher thread. That includes wakeup_flusher_threads() and the functions I've mentioned below. > There's also free_more_memory() and do_try_to_free_pages(). Indeed. So we still have some special cases that want a specific number to be written back globally. > wakeup_flusher_threads() apepars to have been borked. It passes > nr_pages() into *each* bdi hence can write back far more than it was > asked to. > > But seriously, how is the _global_ number of dirty and unstable pages > > a good indicator for the amount of writeback per-bdi or superblock > > anyway? > > It isn't. This appears to have been an attempt to transport the > wakeup_pdflush() functionality into the new wakeup_flusher_threads() > regime. Badly. Unfortunately we don't just use it for wakeup_flusher_threads() but also for various bits of per-bdi and per-sb writeback. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>