On Thu, Apr 26, 2012 at 03:20:34PM -0700, David Rientjes wrote: > On Thu, 26 Apr 2012, Dave Jones wrote: > > > /sys/kernel/mm/ksm/full_scans is increasing constantly > > > > full_scans: 146370 > > pages_shared: 1 > > pages_sharing: 4 > > pages_to_scan: 1250 > > pages_unshared: 867 > > pages_volatile: 1 > > run: 1 > > sleep_millisecs: 20 > > > > full_scans is just a counter of how many times it has scanned mergable > memory so it should be increasing constantly. Whether pages_to_scan == > 1250 and sleep_millisecs == 20 is good for your system is unknown. You > may want to try disabling ksm entirely (echo 0 > /sys/kernel/mm/ksm/run) > to see if it significantly increases responsiveness for your workload. Disabling it stops it hogging the cpu obviously, but there's still 8G of RAM and 1G of used swap sitting around doing something. # free total used free shared buffers cached Mem: 8149440 8025716 123724 0 148 7764 -/+ buffers/cache: 8017804 131636 Swap: 1423736 1066112 357624 SysRq : Show Memory Mem-Info: Node 0 DMA per-cpu: CPU 0: hi: 0, btch: 1 usd: 0 CPU 1: hi: 0, btch: 1 usd: 0 CPU 2: hi: 0, btch: 1 usd: 0 CPU 3: hi: 0, btch: 1 usd: 0 Node 0 DMA32 per-cpu: CPU 0: hi: 186, btch: 31 usd: 19 CPU 1: hi: 186, btch: 31 usd: 175 CPU 2: hi: 186, btch: 31 usd: 140 CPU 3: hi: 186, btch: 31 usd: 182 Node 0 Normal per-cpu: CPU 0: hi: 186, btch: 31 usd: 167 CPU 1: hi: 186, btch: 31 usd: 176 CPU 2: hi: 186, btch: 31 usd: 102 CPU 3: hi: 186, btch: 31 usd: 94 active_anon:1529737 inactive_anon:306307 isolated_anon:0 active_file:1124 inactive_file:2170 isolated_file:0 unevictable:1414 dirty:1 writeback:0 unstable:0 free:35645 slab_reclaimable:10150 slab_unreclaimable:56678 mapped:404 shmem:48 pagetables:45796 bounce:0 Node 0 DMA free:15876kB min:128kB low:160kB high:192kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15652kB mlocked:0kB dirty:0kB writeback:0kB mapped:0kB shmem:0kB slab_reclaimable:0kB slab_unreclaimable:32kB kernel_stack:0kB pagetables:0kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? yes lowmem_reserve[]: 0 3246 8034 8034 Node 0 DMA32 free:62632kB min:27252kB low:34064kB high:40876kB active_anon:2637356kB inactive_anon:527504kB active_file:72kB inactive_file:84kB unevictable:788kB isolated(anon):0kB isolated(file):0kB present:3324200kB mlocked:788kB dirty:0kB writeback:0kB mapped:212kB shmem:72kB slab_reclaimable:944kB slab_unreclaimable:24736kB kernel_stack:336kB pagetables:30028kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:116 all_unreclaimable? no lowmem_reserve[]: 0 0 4788 4788 Node 0 Normal free:64072kB min:40196kB low:50244kB high:60292kB active_anon:3481592kB inactive_anon:697724kB active_file:4424kB inactive_file:8596kB unevictable:4868kB isolated(anon):0kB isolated(file):0kB present:4902912kB mlocked:4868kB dirty:4kB writeback:0kB mapped:1404kB shmem:120kB slab_reclaimable:39656kB slab_unreclaimable:201944kB kernel_stack:2968kB pagetables:153156kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no lowmem_reserve[]: 0 0 0 0 Node 0 DMA: 1*4kB 0*8kB 0*16kB 0*32kB 2*64kB 1*128kB 1*256kB 0*512kB 1*1024kB 1*2048kB 3*4096kB = 15876kB Node 0 DMA32: 214*4kB 124*8kB 65*16kB 55*32kB 32*64kB 15*128kB 9*256kB 7*512kB 7*1024kB 4*2048kB 8*4096kB = 62632kB Node 0 Normal: 670*4kB 573*8kB 402*16kB 468*32kB 171*64kB 73*128kB 31*256kB 12*512kB 1*1024kB 0*2048kB 0*4096kB = 64064kB 5683 total pagecache pages 2341 pages in swap cache Swap cache stats: add 2029253, delete 2026912, find 483987/484568 Free swap = 343568kB Total swap = 1423736kB 2097136 pages RAM 59776 pages reserved 891838 pages shared 1996710 pages non-shared All that anon memory seems to be unaccounted for. [ pid ] uid tgid total_vm rss cpu oom_adj oom_score_adj name [ 351] 0 351 4372 2 3 -17 -1000 udevd [ 818] 0 818 18861 26 0 -17 -1000 sshd [ 1199] 0 1199 4372 2 3 -17 -1000 udevd [ 1214] 0 1214 4371 2 1 -17 -1000 udevd [28963] 0 28963 30988 271 2 0 0 sshd [28987] 81 28987 5439 150 3 -13 -900 dbus-daemon [28990] 0 28990 7085 136 0 0 0 systemd-logind [28995] 1000 28995 31023 373 1 0 0 sshd [29008] 1000 29008 29864 875 2 0 0 bash [29132] 1000 29132 44732 155 3 0 0 sudo [29135] 0 29135 29870 1094 3 0 0 bash [29521] 0 29521 4877 196 0 0 0 systemd-kmsg-sy [29541] 0 29541 27232 211 3 0 0 agetty [29553] 0 29553 29870 875 2 0 0 bash Dave -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>