On Tue, 6 Nov 2007, Rik van Riel wrote: > > I think we could add a flag to the bdi to indicate wheter the backing > > store is a disk file. In fact you can also deduce if if a device has > > no writeback capability set in the BDI. > > > > > Unfortunately this needs to use a page flag, since the > > > PG_swapbacked state needs to be preserved all the way > > > to the point where the page is last removed from the > > > LRU. Trying to derive the status from other info in > > > the page resulted in wrong VM statistics in earlier > > > split VM patchsets. > > > > The bdi may avoid that extra flag. > > The bdi will no longer be accessible by the time a page > makes it to free_hot_cold_page, which is one place in the > kernel where this information is needed.
At that point you need only information about which list the page was put on. Dont we need something like PageLRU -> PageFileLRU and PageMemLRU? The page may change its nature I think? What if a page becomes swap backed? - 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/
