On Tue, 2014-06-10 at 16:33 -0700, Andrew Morton wrote: > > break; > > > > if (nr_file > nr_anon) { > > - unsigned long scan_target = > targets[LRU_INACTIVE_ANON] + > > > - targets[LRU_ACTIVE_ANON] > + 1; > > + nr_to_scan = nr_file - ratio * nr_anon; > > + percentage = nr[LRU_FILE] * 100 / nr_file; > > here, nr_file and nr_anon are derived from the contents of nr[]. But > nr[] was modified in the for_each_evictable_lru() loop, so its > contents > now may differ from what was in targets[]?
nr_to_scan is used for recording the number of pages that should be scanned to keep original *ratio*. We can assume that the value of (nr_file > nr_anon) is true, nr_to_scan should be distribute to nr[LRU_ACTIVE_FILE] and nr[LRU_INACTIVE_FILE] in proportion. nr_file = nr[LRU_ACTIVE_FILE] + nr[LRU_INACTIVE_FILE]; percentage = nr[LRU_FILE] / nr_file; Note that in comparison with *old* percentage, the "new" percentage has the different meaning. It is just used to divide nr_so_scan pages appropriately. thx! cyc -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/