{"id":993,"date":"2018-09-17T19:06:49","date_gmt":"2018-09-17T10:06:49","guid":{"rendered":"https:\/\/chat-messenger.com\/?p=993"},"modified":"2019-06-30T18:44:15","modified_gmt":"2019-06-30T09:44:15","slug":"runtime-totalmemory-freememory","status":"publish","type":"post","link":"https:\/\/chat-messenger.com\/zh\/\u535a\u5ba2\/java\/\u8fd0\u884c\u65f6\u95f4-\u5185\u5b58\u603b\u91cf-\u7a7a\u95f2\u5185\u5b58","title":{"rendered":"\u83b7\u53d6 Java \u5185\u5b58\u4f7f\u7528\u60c5\u51b5"},"content":{"rendered":"<h2 class=\"common_title\"><a name=\"0\">Java <strong>\u5185\u5b58<\/strong>\u83b7\u53d6\u4f7f\u7528\u60c5\u51b5 <strong>Runtime.getRuntime().totalMemory, freeMemory<\/strong><\/a><\/h2>\n<p>\n<strong>Java <\/strong> \u8fd4\u56de\u865a\u62df\u673a\u5185\u5b58\u4fe1\u606f\u7684 \"\u603b\"\u3001\"\u5df2\u7528 \"\u548c \"\u6700\u5927\u53ef\u7528 \"\u4fe1\u606f\u3002<br \/>\n\u6bcf\u4e2a\u9879\u76ee\u7684\u8bf4\u660e\u5982\u4e0b\u3002\n<\/p>\n<ul>\n<li><strong>\u603b\u91d1\u989d<\/strong>...<strong>Runtime.getRuntime().totalMemory()\u3002<\/strong>\u662f\u5206\u914d\u7ed9 Java \u865a\u62df\u673a\u7684\u5185\u5b58\u91cf\u3002<\/li>\n<li><strong>\u4f7f\u7528\u91cf<\/strong>...<strong>Runtime.getRuntime().totalMemory()\u3002<\/strong>\u3000-<strong>Runtime.getRuntime().freeMemory()\u3002<\/strong>\u53d8\u5f97\uff0c<br \/>\n\u5f53\u524d\u5728\u5185\u5b58\u4e2d\u5206\u914d\u7684\u5bf9\u8c61\u7684\u5185\u5b58\u4f7f\u7528\u60c5\u51b5\u3002<\/li>\n<li><strong>\u53ef\u7528\u6700\u5927\u503c<\/strong>...<strong>Runtime.getRuntime().maxMemory()\u3002<\/strong>\u662f Java \u865a\u62df\u673a\u5c1d\u8bd5\u4f7f\u7528\u7684\u6700\u5927\u5185\u5b58\u5bb9\u91cf\u3002<br \/>\n\u5982\u679c\u4f7f\u7528\u91cf\u63a5\u8fd1\u603b\u4f7f\u7528\u91cf\uff0c\u5373\u4f7f\u8fdb\u884c\u4e86\u5783\u573e\u56de\u6536\u4e5f\u6ca1\u6709\u53ef\u7528\u5185\u5b58\uff0cJava \u865a\u62df\u673a\u5c31\u4f1a\u6269\u5c55\u5230 \"\u6700\u5927\u53ef\u7528\"\u3002<\/li>\n<\/ul>\n<h2 class=\"common_title\"><a name=\"1\">\u793a\u4f8b\u7a0b\u5e8f<\/a><\/h2>\n<pre class=\"sample_src\">\/**\r\n * Java \u865a\u62df\u673a\u7684\u603b\u5185\u5b58\u5bb9\u91cf\u548c\u4f7f\u7528\u60c5\u51b5\u3001\r\n * \u8fd4\u56de\u5c1d\u8bd5\u4f7f\u7528\u7684\u6700\u5927\u5185\u5b58\u5bb9\u91cf\u4fe1\u606f\u3002\r\n * \u8fd4\u56de Java \u865a\u62df\u673a\u5185\u5b58\u4fe1\u606f\u3002\r\n *\/\r\npublic static String getMemoryInfo() {\r\n    DecimalFormat f1 = new DecimalFormat(\"#,###KB\")\uff1b\r\n    DecimalFormat f2 = new DecimalFormat(\"##.#\")\uff1b\r\n    long free = Runtime.getRuntime().freeMemory() \/ 1024\uff1b\r\n    long total = Runtime.getRuntime().totalMemory() \/ 1024\uff1b\r\n    long max = Runtime.getRuntime().maxMemory() \/ 1024\uff1b\r\n    long used = total - free\uff1b\r\n    double ratio = (used * 100 \/ (double)total)\uff1b\r\n    \u5b57\u7b26\u4e32 info =\r\n    \"Java \u5185\u5b58\u4fe1\u606f\uff1a\u603b\u5185\u5b58 = \" + f1.format(total) + \",\" +\r\n    \"\u5df2\u7528 = \" + f1.format(used) + \" (\" + f2.format(ratio) + \"%),\" +\r\n    \"\u53ef\u7528\u6700\u5927\u503c = \" + f1.format(max)\uff1b\r\n    \u8fd4\u56de info; }\r\n}\r\n<\/pre>\n<p><script type=\"text\/javascript\" src=\"https:\/\/chat-messenger.com\/js\/common.js?dd12sssas2223\" charset=\"UTF-8\"><\/script><br \/>\n<script type=\"text\/javascript\"> writePR(); <\/script><\/p>\n<h2 class=\"common_title\"><a name=\"2\">\u6267\u884c\u7ed3\u679c 1.<\/a><\/h2>\n<p>\u6267\u884c\u793a\u4f8b<\/p>\n<pre class=\"sample_src\">public static void main(String[] args) {\r\n    System.out.println(getMemoryInfo())\uff1b\r\n}\r\n<\/pre>\n<p>\u8f93\u51fa\u7ed3\u679c<\/p>\n<pre class=\"console\">Java \u5185\u5b58\u4fe1\u606f\uff1a\u603b\u8ba1 = 1,984 KB\uff0c\u4f7f\u7528 = 458 KB (23.1%)\uff0c\u6700\u5927\u53ef\u7528 = 65,088 KB\r\n<\/pre>\n<h2 class=\"common_title\"><a name=\"3\">\u6267\u884c\u7ed3\u679c 2.<\/a><\/h2>\n<p>\u6267\u884c\u793a\u4f8b<br \/>\n\u66f4\u6539 Java \u5806\u5927\u5c0f\u5e76\u8fd0\u884c\u3002<br \/>\nJava \u5806\u5927\u5c0f\u503c\u53ef\u5728 Java \u547d\u4ee4\u9009\u9879\u4e2d\u6307\u5b9a\u3002<\/p>\n<div class=\"point\">\njava -Xms64m -Xmx512m Main <\/p>\n<p>-Xms\u521d\u59cb\u5806\u5927\u5c0f<br \/>\n\u6307\u5b9a\u5206\u914d\u7ed9 Java \u865a\u62df\u673a\u7684\u521d\u59cb\u5185\u5b58\u91cf\u3002\u9ed8\u8ba4\u503c\u4e3a 2 MB\u3002<br \/>\n-Xmx \u6700\u5927\u5806\u5927\u5c0f<br \/>\n\u6307\u5b9a Java \u865a\u62df\u673a\u7684\u6700\u5927\u5185\u5b58\u5206\u914d\u3002\u9ed8\u8ba4\u503c\u4e3a 64 MB\u3002\n<\/div>\n\n<pre class=\"sample_src\">public static void main(String[] args) {\r\n    System.out.println(getMemoryInfo())\uff1b\r\n}\r\n<\/pre>\n<p>\u8f93\u51fa\u7ed3\u679c<\/p>\n<pre class=\"console\">Java \u5185\u5b58\u4fe1\u606f\uff1a\u603b\u5bb9\u91cf = 65,088KB\uff0c\u4f7f\u7528\u91cf = 524KB (0.81TB3T)\uff0c\u6700\u5927\u53ef\u7528\u5bb9\u91cf = 520,256KB\r\n<\/pre>\n<p>\u603b\u8fd0\u884c\u65f6.getRuntime().totalMemory() \"\u4e3a<strong>-Xms\u3002<\/strong>\u548c \"\u6700\u5927\u53ef\u7528 Runtime.getRuntime().maxMemory()\" \u4e2d\u7684<strong>-Xmx<\/strong>\u94fe\u63a5\u5230<\/p>","protected":false},"excerpt":{"rendered":"<p>\u83b7\u53d6 Java \u5185\u5b58\u4f7f\u7528\u60c5\u51b5 Runtime.getRuntime().totalMemory, freeMe [...]<\/p>","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"swell_btn_cv_data":""},"categories":[19],"tags":[],"_links":{"self":[{"href":"https:\/\/chat-messenger.com\/zh\/wp-json\/wp\/v2\/posts\/993"}],"collection":[{"href":"https:\/\/chat-messenger.com\/zh\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/chat-messenger.com\/zh\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/chat-messenger.com\/zh\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/chat-messenger.com\/zh\/wp-json\/wp\/v2\/comments?post=993"}],"version-history":[{"count":9,"href":"https:\/\/chat-messenger.com\/zh\/wp-json\/wp\/v2\/posts\/993\/revisions"}],"predecessor-version":[{"id":3636,"href":"https:\/\/chat-messenger.com\/zh\/wp-json\/wp\/v2\/posts\/993\/revisions\/3636"}],"wp:attachment":[{"href":"https:\/\/chat-messenger.com\/zh\/wp-json\/wp\/v2\/media?parent=993"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/chat-messenger.com\/zh\/wp-json\/wp\/v2\/categories?post=993"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/chat-messenger.com\/zh\/wp-json\/wp\/v2\/tags?post=993"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}