On Mon, 2011-04-11 at 17:19 +0900, KOSAKI Motohiro wrote: > This patch raise zone_reclaim_mode threshold to 30. 30 don't have > specific meaning. but 20 mean one-hop QPI/Hypertransport and such > relatively cheap 2-4 socket machine are often used for tradiotional > server as above. The intention is, their machine don't use > zone_reclaim_mode. I know specifically of pieces of x86 hardware that set the information in the BIOS to '21' *specifically* so they'll get the zone_reclaim_mode behavior which that implies. They've done performance testing and run very large and scary benchmarks to make sure that they _want_ this turned on. What this means for them is that they'll probably be de-optimized, at least on newer versions of the kernel. If you want to do this for particular systems, maybe _that_'s what we should do. Have a list of specific configurations that need the defaults overridden either because they're buggy, or they have an unusual hardware configuration not really reflected in the distance table. -- Dave -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>