On Fri, Aug 16, 2013 at 12:15:21PM -0700, Yinghai Lu wrote: > On Fri, Aug 16, 2013 at 12:01 PM, Russ Anderson <rja@xxxxxxx> wrote: > > On Thu, Aug 15, 2013 at 01:43:48PM -0700, Andrew Morton wrote: > >> On Wed, 14 Aug 2013 22:46:29 -0700 Yinghai Lu <yinghai@xxxxxxxxxx> wrote: > >> > >> > Current early_pfn_to_nid() on arch that support memblock go > >> > over memblock.memory one by one, so will take too many try > >> > near the end. > >> > > >> > We can use existing memblock_search to find the node id for > >> > given pfn, that could save some time on bigger system that > >> > have many entries memblock.memory array. > >> > >> Looks nice. I wonder how much difference it makes. > > > > Here are the timing differences for several machines. > > In each case with the patch less time was spent in __early_pfn_to_nid(). > > > > > > 3.11-rc5 with patch difference (%) > > -------- ---------- -------------- > > UV1: 256 nodes 9TB: 411.66 402.47 -9.19 (2.23%) > > UV2: 255 nodes 16TB: 1141.02 1138.12 -2.90 (0.25%) > > UV2: 64 nodes 2TB: 128.15 126.53 -1.62 (1.26%) > > UV2: 32 nodes 2TB: 121.87 121.07 -0.80 (0.66%) > > Time in seconds. > > > > Thanks. > > 9T one have more entries in memblock.memory? Yes. It is older hardware with smaller DIMMs and more of them. -- Russ Anderson, OS RAS/Partitioning Project Lead SGI - Silicon Graphics Inc rja@xxxxxxx -- 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>