Linus Torvalds wrote: > Tetsuo, mind trying it out and maybe tweaking it a bit for the load > you have? Does it seem to improve on your situation? Yes, I already tried it and just replied to Michal. I tested for one hour using various memory stressing programs. As far as I tested, I did not hit silent hang up ( MemAlloc-Info: X stalling task, 0 dying task, 0 victim task. where X > 0). ---------------------------------------- [ 134.510993] Mem-Info: [ 134.511940] active_anon:408777 inactive_anon:2088 isolated_anon:24 [ 134.511940] active_file:15 inactive_file:24 isolated_file:0 [ 134.511940] unevictable:0 dirty:4 writeback:1 unstable:0 [ 134.511940] slab_reclaimable:3109 slab_unreclaimable:5594 [ 134.511940] mapped:679 shmem:2156 pagetables:2077 bounce:0 [ 134.511940] free:12911 free_pcp:31 free_cma:0 [ 134.521256] Node 0 DMA free:7256kB min:400kB low:500kB high:600kB active_anon:6560kB inactive_anon:180kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15988kB managed:15904kB mlocked:0kB dirty:0kB writeback:0kB mapped:80kB shmem:184kB slab_reclaimable:236kB slab_unreclaimable:296kB kernel_stack:48kB pagetables:556kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? yes [ 134.532779] lowmem_reserve[]: 0 1714 1714 1714 [ 134.534455] Node 0 DMA32 free:44388kB min:44652kB low:55812kB high:66976kB active_anon:1628548kB inactive_anon:8172kB active_file:60kB inactive_file:96kB unevictable:0kB isolated(anon):96kB isolated(file):0kB present:2080640kB managed:1759252kB mlocked:0kB dirty:16kB writeback:4kB mapped:2636kB shmem:8440kB slab_reclaimable:12200kB slab_unreclaimable:22080kB kernel_stack:3584kB pagetables:7752kB unstable:0kB bounce:0kB free_pcp:240kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:1016 all_unreclaimable? yes [ 134.545830] lowmem_reserve[]: 0 0 0 0 [ 134.547404] Node 0 DMA: 16*4kB (UME) 16*8kB (UME) 10*16kB (UME) 6*32kB (UME) 1*64kB (M) 2*128kB (UE) 1*256kB (M) 2*512kB (UE) 3*1024kB (UME) 1*2048kB (U) 0*4096kB = 7264kB [ 134.552766] Node 0 DMA32: 1158*4kB (UME) 638*8kB (UE) 244*16kB (UME) 163*32kB (UE) 73*64kB (UE) 34*128kB (UME) 17*256kB (UME) 10*512kB (UME) 7*1024kB (UM) 0*2048kB 0*4096kB = 44520kB [ 134.558111] Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB [ 134.560358] 2195 total pagecache pages [ 134.562043] 0 pages in swap cache [ 134.563604] Swap cache stats: add 0, delete 0, find 0/0 [ 134.565441] Free swap = 0kB [ 134.567015] Total swap = 0kB [ 134.568628] 524157 pages RAM [ 134.570034] 0 pages HighMem/MovableOnly [ 134.571681] 80368 pages reserved [ 134.573467] 0 pages hwpoisoned ---------------------------------------- Only problem I felt is that the ratio of inactive_file/writeback (shown below) was high (compared to shown above) when I did $ cat < /dev/zero > /tmp/file1 & cat < /dev/zero > /tmp/file2 & cat < /dev/zero > /tmp/file3 & sleep 10; ./a.out; killall cat but I think this patch is better than current code. ---------------------------------------- [ 1135.909600] Mem-Info: [ 1135.910686] active_anon:321011 inactive_anon:4664 isolated_anon:0 [ 1135.910686] active_file:3170 inactive_file:78035 isolated_file:512 [ 1135.910686] unevictable:0 dirty:0 writeback:78618 unstable:0 [ 1135.910686] slab_reclaimable:5739 slab_unreclaimable:6170 [ 1135.910686] mapped:4666 shmem:8300 pagetables:1966 bounce:0 [ 1135.910686] free:12938 free_pcp:0 free_cma:0 [ 1135.925255] Node 0 DMA free:7232kB min:400kB low:500kB high:600kB active_anon:5852kB inactive_anon:196kB active_file:120kB inactive_file:980kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15988kB managed:15904kB mlocked:0kB dirty:0kB writeback:968kB mapped:248kB shmem:388kB slab_reclaimable:316kB slab_unreclaimable:272kB kernel_stack:64kB pagetables:100kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:7444 all_unreclaimable? yes [ 1135.936728] lowmem_reserve[]: 0 1714 1714 1714 [ 1135.938486] Node 0 DMA32 free:44520kB min:44652kB low:55812kB high:66976kB active_anon:1278192kB inactive_anon:18460kB active_file:12560kB inactive_file:313176kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:2080640kB managed:1759252kB mlocked:0kB dirty:0kB writeback:313504kB mapped:18416kB shmem:32812kB slab_reclaimable:22640kB slab_unreclaimable:24408kB kernel_stack:4240kB pagetables:7764kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:2957668 all_unreclaimable? yes [ 1135.950355] lowmem_reserve[]: 0 0 0 0 [ 1135.952011] Node 0 DMA: 7*4kB (U) 14*8kB (UM) 13*16kB (UM) 6*32kB (UME) 1*64kB (M) 4*128kB (UME) 2*256kB (UM) 3*512kB (UME) 2*1024kB (UE) 1*2048kB (M) 0*4096kB = 7260kB [ 1135.957169] Node 0 DMA32: 241*4kB (UE) 929*8kB (UE) 496*16kB (UME) 277*32kB (UE) 135*64kB (UME) 17*128kB (UME) 3*256kB (E) 16*512kB (ME) 0*1024kB 0*2048kB 0*4096kB = 44972kB [ 1135.963047] Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB [ 1135.965472] 90009 total pagecache pages [ 1135.967078] 0 pages in swap cache [ 1135.968581] Swap cache stats: add 0, delete 0, find 0/0 [ 1135.970424] Free swap = 0kB [ 1135.971828] Total swap = 0kB [ 1135.973248] 524157 pages RAM [ 1135.974655] 0 pages HighMem/MovableOnly [ 1135.976230] 80368 pages reserved [ 1135.977745] 0 pages hwpoisoned ---------------------------------------- I can still hit OOM livelock ( MemAlloc-Info: X stalling task, Y dying task, Z victim task. where X > 0 && Y > 0). -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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