{"id":2544,"date":"2018-02-28T16:32:22","date_gmt":"2018-02-28T08:32:22","guid":{"rendered":"http:\/\/www.xttblog.com\/?p=2544"},"modified":"2018-02-28T16:32:22","modified_gmt":"2018-02-28T08:32:22","slug":"jvm%e5%86%85%e5%ad%98%e7%ae%a1%e7%90%86%e4%b9%8bgc%ef%bc%88%e5%9e%83%e5%9c%be%e5%9b%9e%e6%94%b6%ef%bc%89%e7%ad%96%e7%95%a5%e4%b8%8e%e5%8e%9f%e7%90%86","status":"publish","type":"post","link":"https:\/\/www.xttblog.com\/?p=2544","title":{"rendered":"JVM\u5185\u5b58\u7ba1\u7406\u4e4bGC\uff08\u5783\u573e\u56de\u6536\uff09\u7b56\u7565\u4e0e\u539f\u7406"},"content":{"rendered":"<p>\n\t\u5185\u5b58\u7ba1\u7406\u4e00\u76f4\u662f JAVA \u8bed\u8a00\u81ea\u8c6a\u4e0e\u9a84\u50b2\u7684\u8d44\u672c\uff0c\u5b83\u8ba9 JAVA 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class Object {\r\n\t\/\/ \u4e1a\u4f59\u8349\uff1awww.xttblog.com\r\n    Object field = null;\r\n    public static void main(String[] args) {\r\n        Thread thread = new Thread(new Runnable() {\r\n            public void run() {\r\n                Object objectA = new Object();\r\n                Object objectB = new Object();\/\/1\r\n                objectA.field = objectB;\r\n                objectB.field = objectA;\/\/2\r\n                \/\/to do something\r\n                objectA = null;\r\n                objectB = null;\/\/3\r\n            }\r\n        });\r\n        thread.start();\r\n        while (true);\r\n    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\/>\n<\/h2>\n<p>\n\t\u7531\u4e8e\u5f15\u7528\u8ba1\u6570\u7b97\u6cd5\u7684\u7f3a\u9677\uff0c\u6240\u4ee5JVM\u4e00\u822c\u4f1a\u91c7\u7528\u4e00\u79cd\u65b0\u7684\u7b97\u6cd5\uff0c\u53eb\u505a\u6839\u641c\u7d22\u7b97\u6cd5\u3002\u5b83\u7684\u5904\u7406\u65b9\u5f0f\u5c31\u662f\uff0c\u8bbe\u7acb\u82e5\u5e72\u79cd\u6839\u5bf9\u8c61\uff0c\u5f53\u4efb\u4f55\u4e00\u4e2a\u6839\u5bf9\u8c61\u5230\u67d0\u4e00\u4e2a\u5bf9\u8c61\u5747\u4e0d\u53ef\u8fbe\u65f6\uff0c\u5219\u8ba4\u4e3a\u8fd9\u4e2a\u5bf9\u8c61\u662f\u53ef\u4ee5\u88ab\u56de\u6536\u7684\u3002\n<\/p>\n<p>\n\t<img decoding=\"async\" alt=\"JVM \u5783\u573e\u56de\u6536 \u6839\u641c\u7d22\u7b97\u6cd5\" src=\"http:\/\/ocuzluml6.bkt.clouddn.com\/jvm_gc_root.jpg\" style=\"width: 753px;height: 447px\" \/>\n<\/p>\n<p>\n\t\u5c31\u62ff\u4e0a\u56fe\u6765\u8bf4\uff0cObjectD\u548cObjectE\u662f\u4e92\u76f8\u5173\u8054\u7684\uff0c\u4f46\u662f\u7531\u4e8eGC roots\u5230\u8fd9\u4e24\u4e2a\u5bf9\u8c61\u4e0d\u53ef\u8fbe\uff0c\u6240\u4ee5\u6700\u7ec8D\u548cE\u8fd8\u662f\u4f1a\u88ab\u5f53\u505aGC\u7684\u5bf9\u8c61\uff0c\u4e0a\u56fe\u82e5\u662f\u91c7\u7528\u5f15\u7528\u8ba1\u6570\u6cd5\uff0c\u5219A-E\u4e94\u4e2a\u5bf9\u8c61\u90fd\u4e0d\u4f1a\u88ab\u56de\u6536\u3002\n<\/p>\n<p>\n\t\u8bf4\u5230GC roots\uff08GC\u6839\uff09\uff0c\u5728JAVA\u8bed\u8a00\u4e2d\uff0c\u53ef\u4ee5\u5f53\u505aGC roots\u7684\u5bf9\u8c61\u6709\u4ee5\u4e0b\u51e0\u79cd\uff1a\n<\/p>\n<ol>\n<li>\n\t\t\u865a\u62df\u673a\u6808\u4e2d\u7684\u5f15\u7528\u7684\u5bf9\u8c61\u3002\n\t<\/li>\n<li>\n\t\t\u65b9\u6cd5\u533a\u4e2d\u7684\u7c7b\u9759\u6001\u5c5e\u6027\u5f15\u7528\u7684\u5bf9\u8c61\u3002\n\t<\/li>\n<li>\n\t\t\u65b9\u6cd5\u533a\u4e2d\u7684\u5e38\u91cf\u5f15\u7528\u7684\u5bf9\u8c61\u3002\n\t<\/li>\n<li>\n\t\t\u672c\u5730\u65b9\u6cd5\u6808\u4e2dJNI\u7684\u5f15\u7528\u7684\u5bf9\u8c61\u3002\n\t<\/li>\n<\/ol>\n<p>\n\t\u7b2c\u4e00\u548c\u7b2c\u56db\u79cd\u90fd\u662f\u6307\u7684\u65b9\u6cd5\u7684\u672c\u5730\u53d8\u91cf\u8868\uff0c\u7b2c\u4e8c\u79cd\u8868\u8fbe\u7684\u610f\u601d\u6bd4\u8f83\u6e05\u6670\uff0c\u7b2c\u4e09\u79cd\u4e3b\u8981\u6307\u7684\u662f\u58f0\u660e\u4e3afinal\u7684\u5e38\u91cf\u503c\u3002\n<\/p>\n<h2>\n\t\u5783\u573e\u6536\u96c6\u7b97\u6cd5<br 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\/>\n<\/p>\n<p>\n\t\u4e0d\u8fc7\u5783\u573e\u6536\u96c6\u663e\u7136\u8fd8\u9700\u8981\u89e3\u51b3\u540e\u4e24\u4e2a\u95ee\u9898\uff0c\u4ec0\u4e48\u65f6\u5019\u56de\u6536\u4ee5\u53ca\u5982\u4f55\u56de\u6536\u3002\u5728\u6839\u641c\u7d22\u7b97\u6cd5\u7684\u57fa\u7840\u4e0a\uff0c\u73b0\u4ee3\u865a\u62df\u673a\u7684\u5b9e\u73b0\u5f53\u4e2d\uff0c\u5783\u573e\u641c\u96c6\u7684\u7b97\u6cd5\u4e3b\u8981\u6709\u4e09\u79cd\uff0c\u5206\u522b\u662f\u6807\u8bb0-\u6e05\u9664\u7b97\u6cd5\u3001\u590d\u5236\u7b97\u6cd5\u3001\u6807\u8bb0-\u6574\u7406\u7b97\u6cd5\u3002\u8fd9\u4e09\u79cd\u7b97\u6cd5\u90fd\u6269\u5145\u4e86\u6839\u641c\u7d22\u7b97\u6cd5\uff0c\u4e0d\u8fc7\u5b83\u4eec\u7406\u89e3\u8d77\u6765\u8fd8\u662f\u975e\u5e38\u597d\u7406\u89e3\u7684\u3002<\/p>\n<!-- <audio autoplay=\"autoplay\" height=\"100\" width=\"100\" hidden=\"true\"><source src=\"https:\/\/c.coka.la\/orAvPR.mp3\" type=\"audio\/mp3\"\/><\/audio><img decoding=\"async\" src=\"https:\/\/images.weserv.nl\/?url=https:\/\/ws3.sinaimg.cn\/large\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/> --><p><!-- <img decoding=\"async\" src=\"https:\/\/raw.githubusercontent.com\/xmt1139057136\/xttblog\/master\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/>--><img decoding=\"async\" src=\"https:\/\/saas.51autoparts.cn\/api\/admin\/sys-file\/oss\/file?fileName=84db51f8561e448f9a4fda2eff0811f9.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/><\/p><p>\u6700\u540e\uff0c\u6b22\u8fce\u5173\u6ce8\u6211\u7684\u4e2a\u4eba\u5fae\u4fe1\u516c\u4f17\u53f7\uff1a\u4e1a\u4f59\u8349\uff08yyucao\uff09\uff01<b>\u53ef\u52a0\u4f5c\u8005\u5fae\u4fe1\u53f7\uff1a<font color=\"red\">xttblog2<\/font>\u3002\u5907\u6ce8\uff1a\u201c1\u201d\uff0c\u6dfb\u52a0\u535a\u4e3b\u5fae\u4fe1\u62c9\u4f60\u8fdb\u5fae\u4fe1\u7fa4\u3002\u5907\u6ce8\u9519\u8bef\u4e0d\u4f1a\u540c\u610f\u597d\u53cb\u7533\u8bf7\u3002<\/b>\u518d\u6b21\u611f\u8c22\u60a8\u7684\u5173\u6ce8\uff01\u540e\u7eed\u6709\u7cbe\u5f69\u5185\u5bb9\u4f1a\u7b2c\u4e00\u65f6\u95f4\u53d1\u7ed9\u60a8\uff01\u539f\u521b\u6587\u7ae0\u6295\u7a3f\u8bf7\u53d1\u9001\u81f3532009913@qq.com\u90ae\u7bb1\u3002\u5546\u52a1\u5408\u4f5c\u4e5f\u53ef\u6dfb\u52a0\u4f5c\u8005\u5fae\u4fe1\u8fdb\u884c\u8054\u7cfb\uff01<\/p><p>\u672c\u6587\u539f\u6587\u51fa\u5904\uff1a<a href=\"https:\/\/www.xttblog.com\">\u4e1a\u4f59\u8349<\/a>\uff1a &raquo; <a href=\"https:\/\/www.xttblog.com\/?p=2544\">JVM\u5185\u5b58\u7ba1\u7406\u4e4bGC\uff08\u5783\u573e\u56de\u6536\uff09\u7b56\u7565\u4e0e\u539f\u7406<\/a><\/p><!-- <div class=\"bd-reward-stl\"><button id=\"bdRewardBtn\"><span><\/span><\/button><\/div> -->","protected":false},"excerpt":{"rendered":"<p>\u5185\u5b58\u7ba1\u7406\u4e00\u76f4\u662f JAVA \u8bed\u8a00\u81ea\u8c6a\u4e0e\u9a84\u50b2\u7684\u8d44\u672c\uff0c\u5b83\u8ba9 JAVA \u7a0b\u5e8f\u5458\u57fa\u672c\u4e0a\u53ef\u4ee5\u5f7b\u5e95\u5ffd\u7565\u4e0e\u5185\u5b58\u7ba1\u7406\u76f8\u5173\u7684\u7ec6\u8282\uff0c [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[328,69,731,314,75],"class_list":["post-2544","post","type-post","status-publish","format-standard","hentry","category-java","tag-gc","tag-java","tag-jvm","tag-taobaojvm","tag-75"],"_links":{"self":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/2544","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2544"}],"version-history":[{"count":1,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/2544\/revisions"}],"predecessor-version":[{"id":2545,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/2544\/revisions\/2545"}],"wp:attachment":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2544"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2544"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2544"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}