There were some changes of behaviours with THP and KSM statistics demonstrated by this program, http://people.redhat.com/qcai/ksm01.c. There are 3 programs (A, B ,C) to allocate 128M memory each using KSM. A has memory content = 'c'. B has memory content = 'a'. C has memory content = 'a'. Then without THP, pages_shared = 2 pages_sharing = 98285 pages_sharing = 98292 pages_unshared = 0 pages_volatile = 17 pages_to_scan = 98304 sleep_millisecs = 0 with THP, pages_shared is 2. pages_sharing is 18422. pages_unshared is 0. pages_volatile is 8. Later, A has memory content = 'c' B has memory content = 'b' C has memory content = 'a'. Then without THP, pages_shared = 3 pages_sharing = 98296 pages_unshared = 0 pages_volatile = 5 with THP, pages_shared = 3 pages_sharing = 16358 pages_unshared = 0 pages_volatile = 23 Later, A has memory content = 'd' B has memory content = 'd' C has memory content = 'd' Then without THP, pages_shared = 1 pages_sharing = 98274 pages_unshared = 0 pages_volatile = 29 with THP, pages_shared = 1 pages_sharing = 8668 pages_unshared = 0 pages_volatile = 35 Finally, A changes one page to 'e' Then without THP, pages_shared = 1 pages_sharing = 98274 pages_unshared = 1 pages_volatile = 28 with THP, pages_shared = 1 pages_sharing = 8163 pages_unshared = 1 pages_volatile = 27 Are those differences for pages_sharing between with and without THP are expected? CAI Qian -- 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 policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>