{"id":15308,"date":"2017-12-08T09:00:12","date_gmt":"2017-12-08T00:00:12","guid":{"rendered":"http:\/\/www.techscore.com\/blog\/?p=15308"},"modified":"2018-11-14T16:33:42","modified_gmt":"2018-11-14T07:33:42","slug":"how_is_load_average_calculated","status":"publish","type":"post","link":"https:\/\/www.techscore.com\/blog\/2017\/12\/08\/how_is_load_average_calculated\/","title":{"rendered":"Load Average \u306f\u3069\u3046\u3084\u3063\u3066\u7b97\u51fa\u3055\u308c\u3066\u3044\u308b\u306e\u304b"},"content":{"rendered":"<p>\u3053\u308c\u306f <a href=\"http:\/\/www.techscore.com\/blog\/2017\/11\/28\/techscore-advent-calendar-2017\/\">TECHSCORE Advent Calendar 2017<\/a> \u306e8\u65e5\u76ee\u306e\u8a18\u4e8b\u3067\u3059\u3002<\/p>\n<p>\u4eca\u56de\u306f\u3001Load Average \u306f\u5358\u7d14\u306b\u5e73\u5747\u3092\u3068\u3063\u3066\u3044\u308b\u308f\u3051\u3067\u306f\u306a\u3044\u3088\u3001\u3068\u3044\u3046\u8a71\u3092\u3057\u307e\u3059\u3002<\/p>\n<h2>\u306f\u3058\u3081\u306b<\/h2>\n<p>\u30d0\u30c3\u30c1\u30b5\u30fc\u30d0\u306e\u3088\u3046\u306b\u3001\u3042\u308b\u6642\u9593\u5e2f\u3060\u3051\u4e00\u5b9a\u306e CPU \u8ca0\u8377\u304c\u304b\u304b\u308b\u3088\u3046\u306a\u30b5\u30fc\u30d0\u3092\u904b\u7528\u3057\u3066\u3044\u308b\u3068\u3001Load Average \u306e\u30b0\u30e9\u30d5\u304c\u3053\u3093\u306a\u5f62\u306b\u306a\u308b\u306e\u3092\u3088\u304f\u898b\u304b\u3051\u307e\u3059\u3002<\/p>\n<p><a href=\"https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/centos6.png\" rel=\"facebox\" rel=\"attachment wp-att-15309\"><img loading=\"lazy\" class=\"aligncenter size-full wp-image-15309\" src=\"https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/centos6.png\" alt=\"\" width=\"649\" height=\"253\" srcset=\"https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/centos6.png 649w, https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/centos6-300x117.png 300w\" sizes=\"(max-width: 649px) 100vw, 649px\" \/><\/a><\/p>\n<p>\u3053\u306e\u30b0\u30e9\u30d5\u306f CentOS 6 (Kernel 2.6.32-696.16.1.el6.x86_64) \u306e\u30b5\u30fc\u30d0\u3067 <a href=\"https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/centos6-cpu-usage.png\" rel=\"facebox\" target=\"_blank\" rel=\"noopener\">11:05 \u304b\u3089 12:00 \u307e\u3067\u306e\u9593\u3001CPU 1\u30b3\u30a2\u5360\u6709\u3059\u308b\u8ca0\u8377\u3092\u304b\u3051\u305f<\/a>\u3068\u304d\u306e\u3082\u306e\u3067\u3059\u30023\u672c\u306e\u6298\u308c\u7dda\u30b0\u30e9\u30d5\u306f\u305d\u308c\u305e\u308c\u904e\u53bb 1, 5, 15\u5206\u9593\u306e\u5e73\u5747\u8ca0\u8377\u3067\u3059\u3002\u5e73\u5747\u3092\u3068\u308b\u671f\u9593\u304c\u9577\u304f\u306a\u308b\u307b\u3069\u30b0\u30e9\u30d5\u306e\u7acb\u3061\u4e0a\u304c\u308a\u30fb\u7acb\u3061\u4e0b\u304c\u308a\u304c\u7de9\u3084\u304b\u306b\u306a\u308b\u69d8\u5b50\u304c\u898b\u3066\u3068\u308c\u307e\u3059\u3002<\/p>\n<p>\u6b21\u306e\u30b0\u30e9\u30d5\u306f 11:00 \u304b\u3089 11:30 \u307e\u3067\u3092\u62e1\u5927\u3057\u305f\u3082\u306e\u3067\u3059\u3002<\/p>\n<p><a href=\"https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/centos6-rising-edge.png\" rel=\"facebox\" rel=\"attachment wp-att-15310\"><img loading=\"lazy\" class=\"aligncenter size-full wp-image-15310\" src=\"https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/centos6-rising-edge.png\" alt=\"\" width=\"651\" height=\"253\" srcset=\"https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/centos6-rising-edge.png 651w, https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/centos6-rising-edge-300x117.png 300w\" sizes=\"(max-width: 651px) 100vw, 651px\" \/><\/a><\/p>\n<p>5\u5206\u5e73\u5747\u306e\u30b0\u30e9\u30d5\u306b\u7740\u76ee\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002\u904e\u53bb 5\u5206\u9593\u306e\u5358\u7d14\u306a\u5e73\u5747\u3067\u3042\u308c\u3070\u3001\u8ca0\u8377\u3092\u304b\u3051\u306f\u3058\u3081\u3066\u304b\u30895\u5206\u7d4c\u904e\u3057\u305f 11:10 \u306b\u306f Load Average \u304c 1.00 \u306b\u9039\u3063\u3057\u3066\u3044\u3066\u3082\u3088\u3044\u306f\u305a\u3067\u3059\u304c\u3001\u5b9f\u969b\u306f 0.64 \u3067\u3057\u305f\u3002\u3069\u3046\u3057\u3066\u3053\u306e\u3088\u3046\u306a\u30b0\u30e9\u30d5\u306b\u306a\u308b\u3067\u3057\u3087\u3046\u304b\uff1f<\/p>\n<p>\u305d\u308c\u306f\u3001Load Average \u304c\u5358\u7d14\u306a\u5e73\u5747\u3067\u306f\u306a\u3044\u304b\u3089\u3067\u3059\u3002<\/p>\n<p>\u305d\u308c\u3067\u306f\u3001\u3069\u306e\u3088\u3046\u306b\u3057\u3066 Load Average \u3092\u7b97\u51fa\u3057\u3066\u3044\u308b\u306e\u304b\u898b\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<br \/>\n\u4ee5\u4e0b\u3001\u5f15\u7528\u3057\u3066\u3044\u308b\u30bd\u30fc\u30b9\u30b3\u30fc\u30c9\u306f CentOS 6 \u306e kernel-2.6.32-696.16.1.el6 \u306e\u3082\u306e\u3067\u3059\u3002<\/p>\n<h2>Load \u3068\u306f<\/h2>\n<p>Linux \u306e Load \u306f\u3001<\/p>\n<ul>\n<li>TASK_RUNNING \u72b6\u614b\uff08CPU \u4e0a\u3067\u5b9f\u884c\u4e2d\u3001\u3042\u308b\u3044\u306f\u5b9f\u884c\u53ef\u80fd\u3067 CPU \u306e\u5272\u308a\u5f53\u3066\u3092\u5f85\u3063\u3066\u3044\u308b\u72b6\u614b\uff09<\/li>\n<li>TASK_UNINTERRUPTIBLE \u72b6\u614b\uff08\u30c7\u30a3\u30b9\u30afI\/O \u306a\u3069\u3067\u5272\u308a\u8fbc\u307f\u4e0d\u53ef\u306e\u5f85\u3061\u72b6\u614b\uff09<\/li>\n<\/ul>\n<p>\u306e\u3044\u305a\u308c\u304b\u306e\u72b6\u614b\u306b\u3042\u308b\u30d7\u30ed\u30bb\u30b9\u306e\u500b\u6570\u3067\u3059\u3002\uff08\u4ee5\u4e0b\u3001\u3053\u306e\u3088\u3046\u306a\u30d7\u30ed\u30bb\u30b9\u306e\u3053\u3068\u3092\u300cActive \u306a\u30d7\u30ed\u30bb\u30b9\u300d\u3068\u66f8\u304f\u3053\u3068\u306b\u3057\u307e\u3059\u3002\uff09<br \/>\n\u3053\u306e\u3042\u305f\u308a\u306f\u591a\u304f\u306e\u30d6\u30ed\u30b0\u8a18\u4e8b\u3067\u89e3\u8aac\u3055\u308c\u3066\u3044\u308b\u306e\u3067\u3001\u3053\u3053\u3067\u306f\u6df1\u5165\u308a\u3057\u307e\u305b\u3093\u3002<\/p>\n<p>\u3068\u3053\u308d\u3067\u3001Load \u306b TASK_UNINTERRUPTIBLE \u3082\u542b\u3081\u308b\u306e\u306f Linux \u306b\u7279\u6709\u306e\u5b9a\u7fa9\u3060\u305d\u3046\u3067\u3059\u3002\u3069\u3046\u3057\u3066\u305d\u3046\u3059\u308b\u3088\u3046\u306b\u306a\u3063\u305f\u306e\u304b\u306f\u3001<a href=\"http:\/\/www.brendangregg.com\/\" target=\"_blank\" rel=\"noopener\">Brendan Gregg<\/a> \u306e\u30d6\u30ed\u30b0\u8a18\u4e8b \u300c<a href=\"http:\/\/www.brendangregg.com\/blog\/2017-08-08\/linux-load-averages.html\" target=\"_blank\" rel=\"noopener\">Linux Load Averages: Solving the Mystery<\/a>\u300d\u306b\u66f8\u304b\u308c\u3066\u3044\u307e\u3059\u3002\u82f1\u8a9e\u3067\u3059\u304c\u975e\u5e38\u306b\u9762\u767d\u3044\u8a18\u4e8b\u3067\u3059\u306e\u3067\u8208\u5473\u306e\u3042\u308b\u65b9\u306f\u662f\u975e\u8aad\u3093\u3067\u307f\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n<h2>Load Average \u306e\u7b97\u51fa<\/h2>\n<h3>calc_global_load \u95a2\u6570<\/h3>\n<p>Load Average \u306f kernel\/sched.c \u5185\u306e calc_global_load \u95a2\u6570\u3067\u66f4\u65b0\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n<pre>void calc_global_load(void)\r\n{\r\n        unsigned long upd = calc_load_update + 10;\r\n        long active;\r\n\r\n        if (time_before(jiffies, upd))\r\n                return;\r\n\r\n        active = atomic_long_read(&calc_load_tasks);\r\n        active = active > 0 ? active * FIXED_1 : 0;\r\n\r\n        avenrun[0] = calc_load(avenrun[0], EXP_1, active);\r\n        avenrun[1] = calc_load(avenrun[1], EXP_5, active);\r\n        avenrun[2] = calc_load(avenrun[2], EXP_15, active);\r\n\r\n        calc_load_update += LOAD_FREQ;\r\n}<\/pre>\n<p>Active \u306a\u30d7\u30ed\u30bb\u30b9\u6570\u306f calc_load_tasks \u5909\u6570\u3067\u7ba1\u7406\u3055\u308c\u3066\u304a\u308a\u30019\u884c\u76ee\u3067 atomic \u306b\u8aad\u307f\u51fa\u3057\u3066 active \u306b\u4ee3\u5165\u3057\u3066\u3044\u307e\u3059\u3002\u3053\u306e\u3088\u3046\u306b\u307e\u3069\u308d\u3063\u3053\u3057\u3044\u51e6\u7406\u306b\u306a\u3063\u3066\u3044\u308b\u306e\u306f\u3001\u30de\u30eb\u30c1\u30b3\u30a2\u3067\u52d5\u4f5c\u3055\u305b\u308b\u305f\u3081\u3067\u3059\u3002<br \/>\nLoad Average \u306f avenrun[] \u306b\u4fdd\u6301\u3055\u308c\u3066\u3044\u307e\u3059\u3002\u3053\u308c\u306f\u8981\u7d20\u6570 3 \u306e\u914d\u5217\u3067\u3001\u305d\u308c\u305e\u308c 1, 5, 15\u5206\u9593\u306e\u5e73\u5747\u5024\u3092\u683c\u7d0d\u3057\u3066\u3044\u307e\u3059\u3002<br \/>\n\u5b9f\u969b\u306e\u8a08\u7b97\u306f 12\u301c14\u884c\u76ee\u3067\u547c\u3073\u51fa\u3055\u308c\u308b calc_load \u95a2\u6570\u5185\u3067\u884c\u306a\u308f\u308c\u3066\u3044\u307e\u3059\u3002\u3069\u3046\u3084\u3089\u3001Load Average \u306f<\/p>\n<ul>\n<li>\u524d\u56de\u306e Load Average<\/li>\n<li>\u5e73\u5747\u3092\u3068\u308b\u671f\u9593\u3054\u3068\u306b\u5b9a\u3081\u3089\u308c\u305f\u5b9a\u6570\uff08EXP_1, EXP_5, EXP_15\uff09<\/li>\n<li>\u73fe\u5728\u306e Active \u306a\u30d7\u30ed\u30bb\u30b9\u6570<\/li>\n<\/ul>\n<p>\u304b\u3089\u7b97\u51fa\u3055\u308c\u308b\u3088\u3046\u3067\u3059\u3002<\/p>\n<h3>Load Average \u306e\u7b97\u51fa\u3067\u5229\u7528\u3055\u308c\u308b\u5b9a\u6570<\/h3>\n<p>FIXED_1, EXP_1 \u306a\u3069\u306e\u5b9a\u6570\u306f include\/linux\/sched.h \u3067\u5b9a\u7fa9\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n<pre>#define FSHIFT          11              \/* nr of bits of precision *\/\r\n#define FIXED_1         (1<<FSHIFT)     \/* 1.0 as fixed-point *\/\r\n#define LOAD_FREQ       (5*HZ+1)        \/* 5 sec intervals *\/\r\n#define EXP_1           1884            \/* 1\/exp(5sec\/1min) as fixed-point *\/\r\n#define EXP_5           2014            \/* 1\/exp(5sec\/5min) *\/\r\n#define EXP_15          2037            \/* 1\/exp(5sec\/15min) *\/<\/pre>\n<p>calc_load \u95a2\u6570\u306e\u51e6\u7406\u3092\u8ffd\u3044\u304b\u3051\u3066\u3044\u304f\u524d\u306b\u3001\u3053\u308c\u3089\u5b9a\u6570\u306e\u610f\u5473\u3092\u62bc\u3055\u3048\u3066\u304a\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n<p>Load Average \u3092\u7b97\u51fa\u3059\u308b\u969b\u3001\u6570\u5024\u3092 11 \u30d3\u30c3\u30c8\u5de6\u306b\u30b7\u30d5\u30c8\u3055\u305b\u305f\u56fa\u5b9a\u5c0f\u6570\u70b9\u6570\u3092\u4f7f\u3063\u3066\u3044\u307e\u3059\u3002FSHIFT \u306f\u3053\u306e\u30b7\u30d5\u30c8\u3055\u305b\u308b\u30d3\u30c3\u30c8\u6570(\uff1d\u5c0f\u6570\u90e8\u306e\u7cbe\u5ea6)\u3067\u3059\u3002FIXED_1 \u306f\u3053\u306e\u56fa\u5b9a\u5c0f\u6570\u70b9\u6f14\u7b97\u306b\u304a\u3051\u308b 1 \u3092\u610f\u5473\u3057\u3066\u304a\u308a\u3001\u5024\u306f 2048 (1&lt;&lt;11) \u3067\u3059\u3002<br \/>\ncalc_global_load \u95a2\u6570\u306e 10\u884c\u76ee<\/p>\n<pre>active = active > 0 ? active * FIXED_1 : 0;<\/pre>\n<p> \u306f\u3001active \u304c\u6b63\u306e\u3068\u304d\u306b FIXED_1 \u3092\u304b\u3051\u308b\u3053\u3068\u306b\u3088\u3063\u3066\u3001\u56fa\u5b9a\u5c0f\u6570\u70b9\u6570\u306b\u5909\u63db\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n<p>LOAD_FREQ \u306f Load Average \u3092\u66f4\u65b0\u3059\u308b\u9593\u9694\u3067\u3001\u305d\u306e\u5024\u306f 5\u79d2\u306b\u76f8\u5f53\u3057\u307e\u3059\u3002(\u6b63\u78ba\u306b\u306f 5\u79d2 + 1 Tick \u306a\u306e\u3067\u3059\u304c\u3001\u3053\u306e 1 Tick \u306e\u7531\u6765\u306b\u3064\u3044\u3066\u306f\u5272\u611b\u3057\u307e\u3059\u3002\uff09\u78ba\u304b\u306b\u3001uptime \u30b3\u30de\u30f3\u30c9\u3092\u9023\u7d9a\u3057\u3066\u5b9f\u884c\u3057\u3066\u307f\u308b\u3068 5\u79d2\u6bce\u306b\u5024\u304c\u66f4\u65b0\u3055\u308c\u3066\u3044\u304d\u307e\u3059\u3002<\/p>\n<p>EXP_1, EXP_5, EXP_15 \u306f\u305d\u308c\u305e\u308c e<sup>-5\/60<\/sup>, e<sup>-5\/300<\/sup>, e<sup>-5\/900<\/sup> \uff08e \u306f\u30cd\u30a4\u30d4\u30a2\u6570\u3067\u5024\u306f 2.71828...) \u3092\u56fa\u5b9a\u5c0f\u6570\u70b9\u6570\u3068\u3057\u3066\u8868\u73fe\u3057\u305f\u3082\u306e\u3067\u3059\u3002e \u306e\u80a9\u306b\u4e57\u3063\u3066\u3044\u308b\u6307\u6570\u306f\u3001LOAD_FREQ \u306b -1 \u3092\u304b\u3051\u3066\u3001\u5e73\u5747\u3092\u3068\u308b\u671f\u9593\u3067\u5272\u3063\u305f\u3082\u306e\u3067\u3059\u3002\u5177\u4f53\u4f8b\u3068\u3057\u3066 EXP_1 \u306e\u5024\u3092\u8a08\u7b97\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002e<sup>-5\/60<\/sup> \u306e\u5024\u306f\u304a\u3088\u305d 0.92004 \u3067\u3059\u3002\u3053\u308c\u306b FIXED_1 (2048) \u3092\u304b\u3051\u3066 1884.3\u3001\u5c0f\u6570\u90e8\u5206\u3092\u56db\u6368\u4e94\u5165\u3057\u3066 1884 \u304c\u5f97\u3089\u308c\u307e\u3059\u3002<\/p>\n<p>\u3053\u308c\u3067\u5404\u5b9a\u6570\u306e\u610f\u5473\u304c\u628a\u63e1\u3067\u304d\u307e\u3057\u305f\u3002 \u305d\u308c\u3067\u306f\u3001calc_load \u95a2\u6570\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n<h3>calc_load \u95a2\u6570<\/h3>\n<p>calc_load \u95a2\u6570\u3082 kernel\/sched.c \u3067\u5b9a\u7fa9\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n<pre>static unsigned long\r\ncalc_load(unsigned long load, unsigned long exp, unsigned long active)\r\n{\r\n        load *= exp;\r\n        load += active * (FIXED_1 - exp);\r\n        return load >> FSHIFT;\r\n}<\/pre>\n<p>load \u306b\u306f\u524d\u56de\u306e Load Average \u304c\u3001exp \u306b\u306f\u5e73\u5747\u3092\u3068\u308b\u671f\u9593\u306b\u5fdc\u3058\u3066 EXP_1, EXP_5, EXP_15 \u306e\u3044\u305a\u308c\u304b\u304c\u3001active \u306b\u306f Active \u306a\u30d7\u30ed\u30bb\u30b9\u6570\u304c\u305d\u308c\u305e\u308c\u56fa\u5b9a\u5c0f\u6570\u70b9\u6570\u3067\u6e21\u3055\u308c\u307e\u3059\u3002\u95a2\u6570\u5185\u306e\u5f0f\u30921\u884c\u306b\u307e\u3068\u3081\u308b\u3068<\/p>\n<p><center><strong>(load * exp + active * (FIXED_1 - exp)) &gt;&gt; FSHIFT<\/strong><\/center><\/p>\n<p>\u3068\u306a\u308a\u307e\u3059\u3002\u3053\u308c\u3092\u901a\u5e38\u306e\u6f14\u7b97\u306b\u713c\u304d\u76f4\u3059\u3068\u6b21\u306e\u5f0f\u3067\u8868\u308f\u3059\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n<p><center><strong>(\u524d\u56de\u306e Load Average) * e<sup>-5\/T<\/sup> + (\u73fe\u5728\u306e Active \u306a\u30d7\u30ed\u30bb\u30b9\u6570) * (1 - e<sup>-5\/T<\/sup>)<\/strong><br \/>\nT: \u5e73\u5747\u3092\u3068\u308b\u671f\u9593\u306e\u79d2\u6570<\/center><\/p>\n<p>\u3053\u306e\u5f0f\u306f\u3001<a href=\"https:\/\/ja.wikipedia.org\/wiki\/%E7%A7%BB%E5%8B%95%E5%B9%B3%E5%9D%87#.E6.8C.87.E6.95.B0.E7.A7.BB.E5.8B.95.E5.B9.B3.E5.9D.87\">\u6307\u6570\u79fb\u52d5\u5e73\u5747<\/a>\u306e\u8a08\u7b97\u5f0f\u3068\u540c\u3058\u69cb\u9020\u3092\u3057\u3066\u3044\u307e\u3059\u3002<br \/>\nWikipedia \u306e\u89e3\u8aac\u6587\u4e2d\u306e\u8a08\u7b97\u5f0f\u306e\u5e73\u6ed1\u4fc2\u6570 \u03b1 \u3092 (1 - e<sup>-5\/T<\/sup>) \u3068\u3057\u305f\u3082\u306e\u306b\u76f8\u5f53\u3057\u307e\u3059\u3002<\/p>\n<p>\u5b9f\u306f\u3053\u308c\u3001\u5e73\u5747\u3092\u3068\u308b\u671f\u9593\uff081, 5, 15\u5206\uff09\u3067 1\/e \u306b\u6e1b\u8870\u3059\u308b\u6307\u6570\u95a2\u6570\u3067\u904e\u53bb\u30c7\u30fc\u30bf\u3092\u91cd\u307f\u4ed8\u3051\u3057\u3066\u5e73\u5747\u3092\u3068\u308b\u306e\u3068\u540c\u3058\u610f\u5473\u306b\u306a\u308a\u307e\u3059\u3002\u4f8b\u3048\u3070\u30015\u5206\u3067 1\/e \u306b\u6e1b\u8870\u3059\u308b\u6307\u6570\u95a2\u6570\u306f\u4e0b\u56f3\u306e\u3088\u3046\u306a\u66f2\u7dda\u3092\u63cf\u304d\u307e\u3059\u3002\u6a2a\u8ef8\u306f\u7d4c\u904e\u6642\u9593\u3067\u3059\u3002<\/p>\n<p><a href=\"https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/exponential_damping.png\" rel=\"facebox\" rel=\"attachment wp-att-15578\"><img loading=\"lazy\" src=\"https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/exponential_damping.png\" alt=\"\" width=\"565\" height=\"278\" class=\"aligncenter size-full wp-image-15578\" srcset=\"https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/exponential_damping.png 565w, https:\/\/www.techscore.com\/blog\/wp\/wp-content\/uploads\/2017\/12\/exponential_damping-300x148.png 300w\" sizes=\"(max-width: 565px) 100vw, 565px\" \/><\/a><\/p>\n<p>\u7406\u8ad6\u7684\u306b\u306f\u904e\u53bb\u306e\u5168\u671f\u9593\u306b\u3064\u3044\u3066\u5e73\u5747\u3092\u3068\u3063\u3066\u3044\u308b\u3053\u3068\u306b\u306a\u308b\u306e\u3067\u3059\u304c\u30011\/e \u306b\u6e1b\u8870\u3059\u308b\u307e\u3067\u306e\u9593\uff08\u4e0a\u306e\u30b0\u30e9\u30d5\u306e\u7db2\u639b\u3051\u90e8\u5206\uff09\u306e\u5bc4\u4e0e\u304c\u5927\u304d\u306a\u5272\u5408\u3092\u5360\u3081\u308b\u306e\u3067\u3001\u4fbf\u5b9c\u7684\u306b\u305d\u306e\u671f\u9593\u306b\u304a\u3051\u308b\u5e73\u5747\u3068\u547c\u3093\u3067\u3044\u307e\u3059\u3002\u6307\u6570\u95a2\u6570\u306e\u7279\u6b8a\u306a\u6027\u8cea\u306e\u304a\u304b\u3052\u3067\u3001\u524d\u56de\u306e\u5e73\u5747\u5024\u3068\u4eca\u56de\u306e\u5024\u3060\u3051\u304b\u3089\u3053\u306e\u5e73\u5747\u5024\u3092\u7b97\u51fa\u3067\u304d\u307e\u3059\u3002<\/p>\n<p>\u307e\u305f\u3001\u3053\u306e\u3088\u3046\u306b\u3057\u3066 Load Average \u3092\u7b97\u51fa\u3057\u3066\u3044\u308b\u3053\u3068\u304b\u3089\u3001\u6700\u521d\u306b\u304a\u898b\u305b\u3057\u305f\u30b0\u30e9\u30d5\u306e\u7acb\u3061\u4e0a\u304c\u308a\u90e8\u5206\u306e\u66f2\u7dda\u304c<\/p>\n<p><center><strong>1 - e<sup>-t\/T<\/sup><\/strong><\/center><\/p>\n<p>\u3068\u306a\u308b\u3053\u3068\u304c\u5c0e\u3051\u307e\u3059\u3002T \u306f\u5e73\u5747\u3092\u3068\u308b\u671f\u9593\u3001t \u306f\u8ca0\u8377\u3092\u304b\u3051\u59cb\u3081\u3066\u304b\u3089\u306e\u7d4c\u904e\u6642\u9593\u3067\u3059\u3002<br \/>\n5\u5206\u5e73\u5747\u306e 5\u5206\u5f8c\u306e\u5024\u306f 1 - e<sup>-300\/300<\/sup> = 1 - e<sup>-1<\/sup> = 1 - 0.368 = 0.632 \u3068\u306a\u308a\u307e\u3059\u3002 \u3053\u308c\u306f\u5b9f\u6e2c\u5024\u306e 0.64 \u3068\u307b\u307c\u4e00\u81f4\u3057\u307e\u3059\u3002<\/p>\n<h2>\u307e\u3068\u3081<\/h2>\n<p>Load Average \u306f\u6307\u6570\u79fb\u52d5\u5e73\u5747\u3067\u7b97\u51fa\u3055\u308c\u3066\u304a\u308a\u3001\u305d\u306e\u91cd\u307f\u306f\u5e73\u5747\u3092\u3068\u308b\u671f\u9593\uff081, 5, 15\u5206\uff09\u3067 1\/e \u306b\u6e1b\u8870\u3059\u308b\u6307\u6570\u95a2\u6570\u306b\u306a\u3063\u3066\u3044\u308b\u3053\u3068\u304c\u5206\u304b\u308a\u307e\u3057\u305f\u3002\u305d\u306e\u7b97\u51fa\u306e\u904e\u7a0b\u3067\u5fc5\u8981\u306b\u306a\u308b\u30c7\u30fc\u30bf\u306f\u524d\u306e Load Average \u306e\u5024\u3068\u73fe\u5728\u306e Active \u306a\u30d7\u30ed\u30bb\u30b9\u6570\u3060\u3051\u3067\u3042\u308b\u3053\u3068\u3082\u5206\u304b\u308a\u307e\u3057\u305f\u3002\u307e\u305f\u3001\u8a08\u7b97\u306e\u9ad8\u901f\u5316\u306e\u305f\u3081\u306b\u56fa\u5b9a\u5c0f\u6570\u70b9\u6f14\u7b97\u3092\u3057\u3066\u3044\u308b\u3053\u3068\u3082\u898b\u307e\u3057\u305f\u3002<\/p>\n<p>\u5b9f\u306f\u3001Load Average \u3092\u7b97\u51fa\u3059\u308b\u30b3\u30fc\u30c9\u306f\u3044\u307e\u3060\u306b\u6539\u826f\u304c\u7d9a\u3051\u3089\u308c\u3066\u304a\u308a\u30012010\u5e74\u3068 2016\u5e74\u306b\u3061\u3087\u3063\u3068\u3057\u305f\u5909\u66f4\u304c\u52a0\u3048\u3089\u308c\u3066\u3044\u307e\u3059\u3002\u305d\u306e\u305f\u3081\u3001CentOS 7 \u306e Load Average \u306b\u306f\u5c0f\u3055\u306a\u30d0\u30b0\u304c\u3042\u308a\u307e\u3059\u3002\u6b21\u306e\u6a5f\u4f1a\u306b\u306f\u305d\u306e\u3042\u305f\u308a\u306e\u3053\u3068\u3092\u66f8\u304d\u305f\u3044\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u3053\u308c\u306f TECHSCORE Advent Calendar 2017 \u306e8\u65e5\u76ee\u306e\u8a18\u4e8b\u3067\u3059\u3002<\/p>\n<p>\u4eca\u56de\u306f\u3001Load Average \u306f\u5358\u7d14\u306b\u5e73\u5747\u3092\u3068\u3063\u3066\u3044\u308b\u308f\u3051\u3067\u306f\u306a\u3044\u3088\u3001\u3068\u3044\u3046\u8a71\u3092\u3057\u307e\u3059\u3002<br \/><a href=\"https:\/\/www.techscore.com\/blog\/2017\/12\/08\/how_is_load_average_calculated\/\">\u7d9a\u304d\u3092\u8aad\u3080...<\/a><\/p>\n","protected":false},"author":22,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[276],"tags":[141,23],"_links":{"self":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/15308"}],"collection":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/users\/22"}],"replies":[{"embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/comments?post=15308"}],"version-history":[{"count":208,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/15308\/revisions"}],"predecessor-version":[{"id":15601,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/15308\/revisions\/15601"}],"wp:attachment":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/media?parent=15308"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/categories?post=15308"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/tags?post=15308"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}