Мы запускаем сервер XMPP на node.js, на машине с 3,8 ГБ ОЗУ. Вот параметры командной строки, которые мы передаем при вызове node: /opt/ node/bin/node --max-old-space-size = 3000 --trace-gc --trace-gc-verbose main.js
Однако нам часто приходится видеть более 10 секунд gc-пауз в процессе (иногда дольше, чем 1 минута gc паузы, где наш сервер ничего не делает, кроме запуска GC). Когда это происходит, наш процесс зависит от обычного потребления памяти: около 1 ГБ использования кучи. Для процесса существует около 2 ГБ или свободного места, но процесс просто не использует его и тратит минутку, пытаясь освободить память.
Глядя на трассировку gc, заданную параметром --trace-gc-verbose, похоже, что свободное пространство на 2 ГБ помечено как "Большое пространство объекта" и не используется, так как не так много больших объектов. И хотя этот процесс остро нуждается в большей памяти для "Старых указателей" и "Старого пространства данных", эта свободная память из "Большего пространства объектов" не используется.
Вот след, оставленный gc в течение одного из тех периодов, когда в процессе была длительная пауза gc:
91635809 ms: Mark-sweep 968.8 (1039.0) -> 958.5 (1038.0) MB, 1 / 410 ms (+ 2287 ms in 79 steps since start of marking, biggest step 140.227051 ms) [idle notification: finalize incremental] [GC in old space requested]. Memory allocator, used: 1088446464, available: 2124390400 New space, used: 192, available: 8388416 Old pointers, used: 633992112, available: 10460240, waste: 0 Old data space, used: 315819248, available: 149776, waste: 0 Code space, used: 5867936, available: 1271392, waste: 0 Map space, used: 10257976, available: 6384072, waste: 0 Cell space, used: 175936, available: 954304, waste: 0 Large object space, used: 51413600, available: 2123325184 91636499 ms: Scavenge 965.5 (1038.0) -> 964.6 (1038.0) MB, 17 ms (+ 109 ms in 10 steps since last GC) [Runtime::PerformGC]. Memory allocator, used: 1088446464, available: 2124390400 New space, used: 41256, available: 2055896 Old pointers, used: 628458688, available: 15993664, waste: 0 Old data space, used: 315821792, available: 147232, waste: 0 Code space, used: 5904256, available: 1235072, waste: 0 Map space, used: 10263072, available: 6378976, waste: 0 Cell space, used: 175936, available: 954304, waste: 0 Large object space, used: 51413600, available: 2123325184 91637979 ms: Scavenge 966.6 (1038.0) -> 964.7 (1038.0) MB, 1 ms (+ 1404 ms in 43 steps since last GC) [Runtime::PerformGC]. Memory allocator, used: 1088446464, available: 2124390400 New space, used: 76736, available: 2020416 Old pointers, used: 628458688, available: 15993664, waste: 0 Old data space, used: 315845520, available: 123504, waste: 0 Code space, used: 5980576, available: 1158752, waste: 0 Map space, used: 10271416, available: 6370632, waste: 0 Cell space, used: 175936, available: 954304, waste: 0 Large object space, used: 51413600, available: 2123325184 91639088 ms: Mark-sweep 965.2 (1038.0) -> 935.8 (1038.0) MB, 1 / 369 ms (+ 2235 ms in 71 steps since start of marking, biggest step 69.053955 ms) [idle notification: finalize incremental] [GC in old space requested]. Memory allocator, used: 1088446464, available: 2124390400 New space, used: 168, available: 2096984 Old pointers, used: 641099768, available: 3352584, waste: 0 Old data space, used: 315820152, available: 148872, waste: 0 Code space, used: 5862976, available: 1276352, waste: 0 Map space, used: 10256744, available: 6385304, waste: 0 Cell space, used: 175936, available: 954304, waste: 0 Large object space, used: 51413600, available: 2123325184 91640987 ms: Scavenge 966.4 (1038.0) -> 964.5 (1038.0) MB, 1 ms (+ 1275 ms in 36 steps since last GC) [allocation failure]. Memory allocator, used: 1088446464, available: 2124390400 New space, used: 100944, available: 1996208 Old pointers, used: 627957504, available: 16494848, waste: 0 Old data space, used: 315830536, available: 138488, waste: 0 Code space, used: 5951200, available: 1188128, waste: 0 Map space, used: 10266376, available: 6375672, waste: 0 Cell space, used: 175936, available: 954304, waste: 0 Large object space, used: 51413600, available: 2123325184 91641560 ms: Scavenge 966.5 (1038.0) -> 964.8 (1038.0) MB, 2 ms (+ 481 ms in 29 steps since last GC) [Runtime::PerformGC]. Memory allocator, used: 1088446464, available: 2124390400 New space, used: 180712, available: 1916440 Old pointers, used: 627957504, available: 16494848, waste: 0 Old data space, used: 315871432, available: 97592, waste: 0 Code space, used: 6019392, available: 1119936, waste: 0 Map space, used: 10269848, available: 6372200, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2123325184 91642589 ms: Mark-sweep 965.9 (1038.0) -> 947.7 (1038.0) MB, 1 / 371 ms (+ 2369 ms in 89 steps since start of marking, biggest step 67.302002 ms) [idle notification: finalize incremental] [GC in old space requested]. Memory allocator, used: 1088446464, available: 2124390400 New space, used: 264, available: 2096888 Old pointers, used: 639592840, available: 4859512, waste: 0 Old data space, used: 315849408, available: 119616, waste: 0 Code space, used: 5862976, available: 1276352, waste: 0 Map space, used: 10257136, available: 6384912, waste: 0 Cell space, used: 175936, available: 954304, waste: 0 Large object space, used: 51413600, available: 2123325184 91643688 ms: Scavenge 966.4 (1038.0) -> 964.6 (1038.0) MB, 5 ms (+ 356 ms in 21 steps since last GC) [Runtime::PerformGC]. Memory allocator, used: 1088446464, available: 2124390400 New space, used: 144088, available: 1953064 Old pointers, used: 627748368, available: 16703984, waste: 0 Old data space, used: 315864504, available: 104520, waste: 0 Code space, used: 5990240, available: 1149088, waste: 0 Map space, used: 10264248, available: 6377800, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2123325184 91645276 ms: Scavenge 966.5 (1038.0) -> 964.8 (1039.0) MB, 2 ms (+ 1520 ms in 46 steps since last GC) [allocation failure]. Memory allocator, used: 1089495040, available: 2123341824 New space, used: 108192, available: 1988960 Old pointers, used: 627748368, available: 16703984, waste: 0 Old data space, used: 315978760, available: 1022200, waste: 0 Code space, used: 6039008, available: 1100320, waste: 0 Map space, used: 10274216, available: 6367832, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2122276608 91645577 ms: Scavenge 966.6 (1039.0) -> 965.8 (1039.0) MB, 3 ms (+ 263 ms in 23 steps since last GC) [allocation failure]. Memory allocator, used: 1089495040, available: 2123341824 New space, used: 516168, available: 1580984 Old pointers, used: 627843088, available: 16609264, waste: 0 Old data space, used: 316550680, available: 450280, waste: 0 Code space, used: 6039008, available: 1100320, waste: 0 Map space, used: 10275280, available: 6366768, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2122276608 91645645 ms: Scavenge 967.3 (1039.0) -> 966.8 (1039.0) MB, 5 ms (+ 8 ms in 16 steps since last GC) [allocation failure]. Memory allocator, used: 1089495040, available: 2123341824 New space, used: 1012304, available: 3182000 Old pointers, used: 627968088, available: 16484264, waste: 0 Old data space, used: 316947304, available: 53656, waste: 0 Code space, used: 6039008, available: 1100320, waste: 0 Map space, used: 10275280, available: 6366768, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2122276608 91645948 ms: Scavenge 969.8 (1039.0) -> 968.6 (1041.0) MB, 9 ms (+ 188 ms in 35 steps since last GC) [allocation failure]. Memory allocator, used: 1091592192, available: 2121244672 New space, used: 1032320, available: 3161984 Old pointers, used: 628219008, available: 16233344, waste: 0 Old data space, used: 318537928, available: 526904, waste: 0 Code space, used: 6039264, available: 1100064, waste: 0 Map space, used: 10276232, available: 6365816, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2120179456 91646093 ms: Scavenge 971.6 (1041.0) -> 970.5 (1042.0) MB, 13 ms (+ 36 ms in 30 steps since last GC) [Runtime::PerformGC]. Memory allocator, used: 1092640768, available: 2120196096 New space, used: 2044456, available: 6344152 Old pointers, used: 628437424, available: 16014928, waste: 0 Old data space, used: 319366376, available: 730392, waste: 0 Code space, used: 6039264, available: 1100064, waste: 0 Map space, used: 10276232, available: 6365816, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2119130880 91646306 ms: Scavenge 976.5 (1042.0) -> 974.7 (1044.0) MB, 1 / 14 ms (+ 114 ms in 67 steps since last GC) [allocation failure]. Memory allocator, used: 1094737920, available: 2118098944 New space, used: 2064112, available: 6324496 Old pointers, used: 630440024, available: 14012328, waste: 0 Old data space, used: 321653384, available: 507256, waste: 0 Code space, used: 6055936, available: 1083392, waste: 0 Map space, used: 10278192, available: 6363856, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2117033728 91646386 ms: Scavenge 980.6 (1044.0) -> 979.2 (1046.0) MB, 12 ms (+ 10 ms in 64 steps since last GC) [allocation failure]. Memory allocator, used: 1096835072, available: 2116001792 New space, used: 4127736, available: 12649480 Old pointers, used: 631182984, available: 13269368, waste: 0 Old data space, used: 323586008, available: 638504, waste: 0 Code space, used: 6055936, available: 1083392, waste: 0 Map space, used: 10278192, available: 6363856, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2114936576 Limited new space size due to high promotion rate: 1 MB 91646810 ms: Mark-sweep 979.2 (1046.0) -> 973.2 (1049.0) MB, 1 / 422 ms (+ 2500 ms in 303 steps since start of marking, biggest step 0.122070 ms) [StackGuard GC request] [GC in old space requested]. Memory allocator, used: 1099980800, available: 2112856064 New space, used: 192, available: 1048384 Old pointers, used: 636894816, available: 9621408, waste: 0 Old data space, used: 325256448, available: 0, waste: 0 Code space, used: 5860928, available: 1278400, waste: 0 Map space, used: 10257976, available: 6384072, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2111790848 91646825 ms: Scavenge 974.2 (1049.0) -> 979.0 (1049.0) MB, 7 ms [allocation failure]. Memory allocator, used: 1099980800, available: 2112856064 New space, used: 257960, available: 790616 Old pointers, used: 635948464, available: 10567760, waste: 0 Old data space, used: 325256448, available: 0, waste: 0 Code space, used: 5873440, available: 1265888, waste: 0 Map space, used: 10258536, available: 6383512, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2111790848 91646834 ms: Scavenge 979.7 (1049.0) -> 980.0 (1049.0) MB, 2 ms [allocation failure]. Memory allocator, used: 1099980800, available: 2112856064 New space, used: 257968, available: 790608 Old pointers, used: 635671408, available: 10844816, waste: 0 Old data space, used: 325256448, available: 0, waste: 0 Code space, used: 5873440, available: 1265888, waste: 0 Map space, used: 10258536, available: 6383512, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2111790848 91646842 ms: Scavenge 980.7 (1049.0) -> 980.6 (1049.0) MB, 2 ms [allocation failure]. Memory allocator, used: 1099980800, available: 2112856064 New space, used: 257960, available: 790616 Old pointers, used: 635493872, available: 11022352, waste: 0 Old data space, used: 325256448, available: 0, waste: 0 Code space, used: 5873440, available: 1265888, waste: 0 Map space, used: 10258536, available: 6383512, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2111790848 91646849 ms: Scavenge 981.3 (1049.0) -> 981.2 (1049.0) MB, 1 ms [allocation failure]. Memory allocator, used: 1099980800, available: 2112856064 New space, used: 257968, available: 790608 Old pointers, used: 635981640, available: 10534584, waste: 0 Old data space, used: 325256448, available: 0, waste: 0 Code space, used: 5873440, available: 1265888, waste: 0 Map space, used: 10258536, available: 6383512, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2111790848 91646863 ms: Scavenge 981.9 (1049.0) -> 981.6 (1051.0) MB, 1 ms [allocation failure]. Memory allocator, used: 1102077952, available: 2110758912 New space, used: 257960, available: 790616 Old pointers, used: 637013288, available: 10534872, waste: 0 Old data space, used: 326288384, available: 0, waste: 0 Code space, used: 5873440, available: 1265888, waste: 0 Map space, used: 10258536, available: 6383512, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2109693696 91651639 ms: Mark-sweep 981.6 (1051.0) -> 924.7 (1051.0) MB, 1 / 4775 ms [last resort gc]. Memory allocator, used: 1102077952, available: 2110758912 New space, used: 96, available: 1048480 Old pointers, used: 626794192, available: 20753968, waste: 0 Old data space, used: 275760200, available: 50528184, waste: 0 Code space, used: 6182208, available: 957120, waste: 0 Map space, used: 10257808, available: 6384240, waste: 0 Cell space, used: 176192, available: 954048, waste: 0 Large object space, used: 51413600, available: 2109693696 91663655 ms: Mark-sweep 924.7 (1051.0) -> 924.7 (1050.0) MB, 1 / 12015 ms [last resort gc]. Memory allocator, used: 1101029376, available: 2111807488 New space, used: 0, available: 1048576 Old pointers, used: 626169464, available: 21378696, waste: 0 Old data space, used: 275759960, available: 49496488, waste: 0 Code space, used: 5850624, available: 1288704, waste: 0 Map space, used: 10257808, available: 6384240, waste:
Есть ли какая-то настройка, которую я могу сделать, чтобы лучше настроить управление памятью V8? Любые идеи о том, что может здесь помочь?
