{"id":4548,"date":"2018-04-05T14:16:09","date_gmt":"2018-04-05T05:16:09","guid":{"rendered":"https:\/\/blog.bitmeister.jp\/?p=4548"},"modified":"2018-04-11T10:41:47","modified_gmt":"2018-04-11T01:41:47","slug":"%e8%aa%a4%e3%81%a3%e3%81%9f%e4%b8%a6%e5%88%97%e5%8c%96%e3%81%ab%e3%82%88%e3%82%8b%e6%80%a7%e8%83%bd%e5%8a%a3%e5%8c%96%ef%bc%88%e3%81%9d%e3%81%ae%ef%bc%92%ef%bc%89","status":"publish","type":"post","link":"https:\/\/blog.bitmeister.jp\/?p=4548","title":{"rendered":"\u8aa4\u3063\u305f\u4e26\u5217\u5316\u306b\u3088\u308b\u6027\u80fd\u52a3\u5316\uff08\u305d\u306e\uff12\uff09"},"content":{"rendered":"<p><a href=\"https:\/\/blog.bitmeister.jp\/?p=4525\">\u524d\u56de\u306e\u8a18\u4e8b<\/a>\u306b\u5f15\u304d\u7d9a\u3044\u3066\u3001\u30de\u30eb\u30c1\u30b9\u30ec\u30c3\u30c9\u30d7\u30ed\u30b0\u30e9\u30e0\u306e\u6027\u80fd\u306b\u3064\u3044\u3066\u3067\u3059\u3002\u524d\u56de\u306f\u300c\u30b3\u30f3\u30c6\u30ad\u30b9\u30c8\u30b9\u30a4\u30c3\u30c1\u30f3\u30b0\u3084\u6392\u4ed6\u5236\u5fa1\u306e\u30aa\u30fc\u30d0\u30d8\u30c3\u30c9\u306b\u898b\u5408\u3046\u51e6\u7406\u3067\u306a\u3051\u308c\u3070\u4e26\u5217\u5316\u306f\u9006\u52b9\u679c\u300d\u3068\u3044\u3046\u3053\u3068\u304c\u308f\u304b\u308a\u307e\u3057\u305f\u3002\u4eca\u56de\u306fmutex\u306e\u30ed\u30c3\u30af\u7372\u5f97\u3068\u958b\u653e\u306b\u3064\u3044\u3066\u7c21\u5358\u306a\u5b9f\u9a13\u3057\u307e\u3059\u3002<\/p>\n<p><!--more--><\/p>\n<p>\u4f7f\u3046\u30d7\u30ed\u30b0\u30e9\u30e0&#8221;mutex_test.c&#8221;\u306fC\u8a00\u8a9e\u3067\u66f8\u304b\u308c\u305f\u30de\u30eb\u30c1\u30b9\u30ec\u30c3\u30c9\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u3001\u8d77\u52d5\u3059\u308b\u306810\u500b\u306e\u30b9\u30ec\u30c3\u30c9\u3092\u8d77\u3053\u3057\u3001\u305d\u308c\u305e\u308c\u306e\u30b9\u30ec\u30c3\u30c9\u304c\u5171\u6709\u5909\u6570\u3092100\u4e07\u56de\u30ab\u30a6\u30f3\u30c8\u30a2\u30c3\u30d7\u3057\u307e\u3059\u3002\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u30bb\u30af\u30b7\u30e7\u30f3\u306f\u5f53\u7136\u77ed\u3044\u306b\u8d8a\u3057\u305f\u3053\u3068\u306f\u306a\u3044\u3068\u3044\u3046\u5b89\u76f4\u306a\u8003\u3048\u3067\u3001\u30ab\u30a6\u30f3\u30c8\u30a2\u30c3\u30d7\u6bce\u306b\u30ed\u30c3\u30af\u306e\u7372\u5f97\u3068\u958b\u653e\u3092\u884c\u3063\u3066\u3044\u307e\u3059\u3002<\/p>\n<pre class=\"brush: cpp; gutter: false; title: ; notranslate\" title=\"\">\r\n#include &lt;stdio.h&gt;\r\n#include &lt;pthread.h&gt;\r\n\r\n\r\nstruct params {\r\n    int *i; \r\n    pthread_mutex_t *mut;\r\n};\r\n\r\nvoid *func(void *arg) {\r\n    int j;\r\n    struct params *prm = (struct params *) arg;\r\n\r\n    for (j = 0; j &lt; 1000000; j++) {\r\n        pthread_mutex_lock(prm-&gt;mut);\r\n        (*(int *)prm-&gt;i)++; \/\/ counts up\r\n        pthread_mutex_unlock(prm-&gt;mut);\r\n    }   \r\n\r\n    return NULL;\r\n}\r\n\r\nint main() {\r\n    int n = 0, x = 0;\r\n    pthread_t th&#x5B;10];\r\n    pthread_mutex_t mut = PTHREAD_MUTEX_INITIALIZER;\r\n    struct params prm = {&amp;x, &amp;mut};\r\n\r\n    for (n = 0; n &lt; 10; n++)\r\n        pthread_create(&amp;th&#x5B;n], NULL, func, &amp;prm);\r\n\r\n    for (n = 0; n &lt; 10; n++)\r\n        pthread_join(th&#x5B;n], NULL);\r\n\r\n    printf(&quot;%d\\n&quot;, x); \r\n\r\n    return 0;\r\n}\r\n<\/pre>\n<p>\u3053\u306e\u30b3\u30fc\u30c9\u3092\u30b3\u30f3\u30d1\u30a4\u30eb\u3057\u3001time\u30b3\u30de\u30f3\u30c9\u3092\u565b\u307e\u305b\u3066\u5b9f\u884c\u3059\u308b\u3068\u3001<\/p>\n<pre class=\"brush: bash; gutter: false; title: ; notranslate\" title=\"\">\r\n$ gcc mutex_test.c -lpthread -Wall\r\n$ time .\/a.out \r\n10000000\r\n\r\nreal\t0m2.117s\r\nuser\t0m1.272s\r\nsys\t0m14.747s\r\n<\/pre>\n<p>1000\u4e07\u56de\u306e\u30ab\u30a6\u30f3\u30c8\u30a2\u30c3\u30d7\u306b16\u79d2\u3082\u306eCPU\u6642\u9593\u3092\u6d88\u8cbb\u3057\u3066\u3057\u307e\u3044\u307e\u3059\u3002\u3055\u3066\u3001\u3053\u3053\u307e\u3067\u306f\u524d\u56de\u3068\u540c\u3058\u3067\u3059\u3002<\/p>\n<p>\u78ba\u304b\u306b\u3001\u30ed\u30c3\u30af\u7372\u5f97\u306e\u305f\u3081\u306e\u5f85\u3061\u6642\u9593\u3092\u5c11\u306a\u304f\u3059\u308b\u305f\u3081\u306b\u306f\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u30bb\u30af\u30b7\u30e7\u30f3\u306f\u77ed\u3044\u307b\u3046\u304c\u3088\u3044\u3067\u3059\u3002\u3057\u304b\u3057\u3001\u904e\u6fc0\u306b\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u30bb\u30af\u30b7\u30e7\u30f3\u3092\u5206\u65ad\u3057\u3066\u4f55\u5ea6\u3082\u30ed\u30c3\u30af\u306e\u7372\u5f97\u3068\u958b\u653e\u3092\u7e70\u308a\u8fd4\u3059\u306e\u306f\u8aa4\u308a\u3067\u3059\u3002\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u30bb\u30af\u30b7\u30e7\u30f3\u5185\u306e\u51e6\u7406\u6642\u9593\u3068\u6392\u4ed6\u5236\u5fa1\u81ea\u4f53\u306b\u95a2\u308f\u308b\u51e6\u7406\u6642\u9593\u3092\u5929\u79e4\u306b\u304b\u3051\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u3053\u306e\u30b3\u30fc\u30c9\u3067\u306f1000\u4e07\u56de\u306e\u30ab\u30a6\u30f3\u30c8\u30a2\u30c3\u30d7\u306e\u305f\u3081\u306b\u300110\u500b\u306e\u30b9\u30ec\u30c3\u30c9\u304c\u305d\u308c\u305e\u308c100\u4e07\u56de\u3082\u30ed\u30c3\u30af\u3092\u596a\u3044\u5408\u3063\u3066\u3044\u308b\u308f\u3051\u3067\u3059\u3002<\/p>\n<p>\u305d\u3093\u306a\u3053\u3068\u3092\u3059\u308b\u304f\u3089\u3044\u306a\u3089\u300110\u500b\u306e\u30b9\u30ec\u30c3\u30c9\u304c\u306f\u3058\u3081\u306b1\u56de\u3060\u3051\u30ed\u30c3\u30af\u3092\u7372\u5f97\u3057\u3066\u3001100\u4e07\u56de\u306e\u30ab\u30a6\u30f3\u30c8\u30a2\u30c3\u30d7\u3057\u305f\u5f8c\u306b\u30ed\u30c3\u30af\u3092\u958b\u653e\u3059\u308b\u307b\u3046\u304c\u3088\u307b\u3069\u52b9\u7387\u7684\u3067\u3059\u3002\u305d\u306e\u3088\u3046\u306b\u30b3\u30fc\u30c9\u3092\u66f8\u304d\u63db\u3048\u3066\u3001<\/p>\n<pre class=\"brush: cpp; gutter: false; title: ; notranslate\" title=\"\">\r\nvoid *func(void *arg) {\r\n    int j;\r\n    struct params *prm = (struct params *) arg;\r\n\r\n    pthread_mutex_lock(prm-&gt;mut);\r\n    for (j = 0; j &lt; 1000000; j++) {\r\n        \/\/ pthread_mutex_lock(prm-&gt;mut);\r\n        (*(int *)prm-&gt;i)++; \/\/ counts up\r\n        \/\/ pthread_mutex_unlock(prm-&gt;mut);\r\n    }\r\n    pthread_mutex_unlock(prm-&gt;mut);\r\n\r\n    return NULL;\r\n}\r\n<\/pre>\n<p>\u5b9f\u884c\u3059\u308b\u3068\u3001<\/p>\n<pre class=\"brush: bash; gutter: false; title: ; notranslate\" title=\"\">\r\n$ gcc mutex_test.c -lpthread -Wall\r\n$ time .\/a.out \r\n10000000\r\n\r\nreal\t0m0.031s\r\nuser\t0m0.031s\r\nsys\t0m0.000s\r\n<\/pre>\n<p>0.031\u79d2\u3002500\u500d\u9ad8\u901f\u306b\u306a\u308a\u307e\u3057\u305f\u3002\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u30bb\u30af\u30b7\u30e7\u30f3\u306f\u77ed\u3044\u65b9\u304c\u3088\u3044\u3067\u3059\u304c\u3001\u77ed\u304f\u3059\u308b\u305f\u3081\u306b\u5206\u65ad\u3059\u308b\u3068\u6392\u4ed6\u5236\u5fa1\u306e\u30b3\u30b9\u30c8\u304c\u5897\u52a0\u3059\u308b\u3053\u3068\u306f\u982d\u306b\u5165\u308c\u3066\u304a\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n<p><a href=\"https:\/\/blog.bitmeister.jp\/?p=4561\">\u6b21\u56de<\/a>\u306f\u3001\u30a4\u30f3\u30af\u30ea\u30e1\u30f3\u30c8\u3060\u3051\u306a\u3089mutex\u307b\u3069\u30ea\u30c3\u30c1\u306a\u6392\u4ed6\u5236\u5fa1\u306f\u5fc5\u8981\u306a\u3044\u3088\u306d\u3068\u3044\u3046\u304a\u8a71\u3067\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u524d\u56de\u306e\u8a18\u4e8b\u306b\u5f15\u304d\u7d9a\u3044\u3066\u3001\u30de\u30eb\u30c1\u30b9\u30ec\u30c3\u30c9\u30d7\u30ed\u30b0\u30e9\u30e0\u306e\u6027\u80fd\u306b\u3064\u3044\u3066\u3067\u3059\u3002\u524d\u56de\u306f\u300c\u30b3\u30f3\u30c6\u30ad\u30b9\u30c8\u30b9\u30a4\u30c3\u30c1\u30f3\u30b0\u3084\u6392\u4ed6\u5236\u5fa1\u306e\u30aa\u30fc\u30d0\u30d8\u30c3\u30c9\u306b\u898b\u5408\u3046\u51e6\u7406\u3067\u306a\u3051\u308c\u3070\u4e26\u5217\u5316\u306f\u9006\u52b9\u679c\u300d\u3068\u3044\u3046\u3053\u3068\u304c\u308f\u304b\u308a\u307e\u3057\u305f\u3002\u4eca\u56de\u306fmutex\u306e\u30ed\u30c3\u30af\u7372\u5f97\u3068\u958b [&hellip;]<\/p>\n","protected":false},"author":8,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17],"tags":[],"class_list":["post-4548","post","type-post","status-publish","format-standard","hentry","category-tech"],"_links":{"self":[{"href":"https:\/\/blog.bitmeister.jp\/index.php?rest_route=\/wp\/v2\/posts\/4548","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.bitmeister.jp\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.bitmeister.jp\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.bitmeister.jp\/index.php?rest_route=\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.bitmeister.jp\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4548"}],"version-history":[{"count":9,"href":"https:\/\/blog.bitmeister.jp\/index.php?rest_route=\/wp\/v2\/posts\/4548\/revisions"}],"predecessor-version":[{"id":4588,"href":"https:\/\/blog.bitmeister.jp\/index.php?rest_route=\/wp\/v2\/posts\/4548\/revisions\/4588"}],"wp:attachment":[{"href":"https:\/\/blog.bitmeister.jp\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4548"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.bitmeister.jp\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4548"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.bitmeister.jp\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4548"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}