{"id":5059,"date":"2020-07-21T22:22:45","date_gmt":"2020-07-21T14:22:45","guid":{"rendered":"https:\/\/www.xttblog.com\/?p=5059"},"modified":"2020-07-21T22:22:45","modified_gmt":"2020-07-21T14:22:45","slug":"8-%e5%b8%b8%e8%a7%81%e7%9a%84-oom-%e4%bb%a3%e7%a0%81%e5%92%8c%e5%bc%82%e5%b8%b8%e5%88%86%e6%9e%90","status":"publish","type":"post","link":"https:\/\/www.xttblog.com\/?p=5059","title":{"rendered":"8 \u5e38\u89c1\u7684 OOM \u4ee3\u7801\u548c\u5f02\u5e38\u5206\u6790"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">\u5728\u300aJava\u865a\u62df\u673a\u89c4\u8303\u300b\u7684\u89c4\u5b9a\u91cc\uff0c\u9664\u4e86\u7a0b\u5e8f\u8ba1\u6570\u5668\u5916\uff0c\u865a\u62df\u673a\u5185\u5b58\u7684\u5176\u4ed6\u51e0\u4e2a\u8fd0\u884c\u65f6\u533a\u57df\u90fd\u6709\u53d1\u751f OutOfMemoryError \u5f02\u5e38\u7684\u53ef\u80fd\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/gitee.com\/xmtblog\/img\/raw\/master\/2020\/OOM1.png\" alt=\"\" \/><figcaption>10 \u79cd OOM<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u672c\u7bc7\u4e3b\u8981\u5305\u62ec\u5982\u4e0b OOM \u7684\u4ecb\u7ecd\u548c\u793a\u4f8b\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>java.lang.StackOverflowError<\/li><li>java.lang.OutOfMemoryError: Java heap space<\/li><li>java.lang.OutOfMemoryError: GC overhead limit exceeded<\/li><li>java.lang.OutOfMemoryError&#8211;&gt;Metaspace<\/li><li>java.lang.OutOfMemoryError: Direct buffer memory<\/li><li>java.lang.OutOfMemoryError: unable to create new native thread<\/li><li>java.lang.OutOfMemoryError\uff1aMetaspace<\/li><li>java.lang.OutOfMemoryError: Requested array size exceeds VM limit<\/li><li>java.lang.OutOfMemoryError: Out of swap space<\/li><li>java.lang.OutOfMemoryError\uff1aKill process or sacrifice child<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4eec\u5e38\u8bf4\u7684 OOM \u5f02\u5e38\uff0c\u5176\u5b9e\u662f Error\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/gitee.com\/xmtblog\/img\/raw\/master\/2020\/oom0.png\" alt=\"\" \/><figcaption>OOM \u5f02\u5e38\u7684\u5173\u7cfb\u56fe<\/figcaption><\/figure><\/div>\n\n\n\n<h2 class=\"wp-block-heading\">StackOverflowError<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5148\u5199\u4e2a bug \u4ea7\u751f StackOverflowError\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>public class StackOverflowErrorDemo {\n    public static void main(String[] args) {\n        javaKeeper();\n    }\n    private static void javaKeeper() {\n        javaKeeper();\n    }\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">JVM \u8fd0\u884c\u65f6\u6570\u636e\u533a\uff0cJVM \u865a\u62df\u673a\u6808\u662f\u6709\u6df1\u5ea6\u7684\uff0c\u5728\u6267\u884c\u65b9\u6cd5\u7684\u65f6\u5019\u4f1a\u4f34\u968f\u7740\u5165\u6808\u548c\u51fa\u6808\uff0c\u4e0a\u8fb9\u7684\u65b9\u6cd5\u53ef\u4ee5\u770b\u5230\uff0cmain \u65b9\u6cd5\u6267\u884c\u540e\u4e0d\u505c\u7684\u9012\u5f52\uff0c\u8fdf\u65e9\u628a\u6808\u6491\u7206\u4e86<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>Exception in thread \"main\" java.lang.StackOverflowError\n at oom.StackOverflowErrorDemo.javaKeeper(StackOverflowErrorDemo.java:15)<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0b\u9762\u6211\u4eec\u5206\u6790\u4e00\u4e0b\u4ea7\u751f\u8fd9\u4e2a\u95ee\u9898\u7684\u539f\u56e0\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u65e0\u9650\u9012\u5f52\u5faa\u73af\u8c03\u7528\uff08\u6700\u5e38\u89c1\u539f\u56e0\uff09\uff0c\u8981\u65f6\u523b\u6ce8\u610f\u4ee3\u7801\u4e2d\u662f\u5426\u6709\u4e86\u5faa\u73af\u8c03\u7528\u65b9\u6cd5\u800c\u65e0\u6cd5\u9000\u51fa\u7684\u60c5\u51b5<\/li><li>\u6267\u884c\u4e86\u5927\u91cf\u65b9\u6cd5\uff0c\u5bfc\u81f4\u7ebf\u7a0b\u6808\u7a7a\u95f4\u8017\u5c3d<\/li><li>\u65b9\u6cd5\u5185\u58f0\u660e\u4e86\u6d77\u91cf\u7684\u5c40\u90e8\u53d8\u91cf<\/li><li>native \u4ee3\u7801\u6709\u6808\u4e0a\u5206\u914d\u7684\u903b\u8f91\uff0c\u5e76\u4e14\u8981\u6c42\u7684\u5185\u5b58\u8fd8\u4e0d\u5c0f\uff0c\u6bd4\u5982 java.net.SocketInputStream.read0 \u4f1a\u5728\u6808\u4e0a\u8981\u6c42\u5206\u914d\u4e00\u4e2a 64KB \u7684\u7f13\u5b58\uff0864\u4f4d Linux\uff09<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u77e5\u9053\u4e86\u539f\u56e0\uff0c\u5c31\u5e94\u8be5\u77e5\u9053\u5982\u4f55\u907f\u514d\u548c\u89e3\u51b3\u4e86\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u4fee\u590d\u5f15\u53d1\u65e0\u9650\u9012\u5f52\u8c03\u7528\u7684\u5f02\u5e38\u4ee3\u7801\uff0c \u901a\u8fc7\u7a0b\u5e8f\u629b\u51fa\u7684\u5f02\u5e38\u5806\u6808\uff0c\u627e\u51fa\u4e0d\u65ad\u91cd\u590d\u7684\u4ee3\u7801\u884c\uff0c\u6309\u56fe\u7d22\u9aa5\uff0c\u4fee\u590d\u65e0\u9650\u9012\u5f52 Bug<\/li><li>\u6392\u67e5\u662f\u5426\u5b58\u5728\u7c7b\u4e4b\u95f4\u7684\u5faa\u73af\u4f9d\u8d56\uff08\u5f53\u4e24\u4e2a\u5bf9\u8c61\u76f8\u4e92\u5f15\u7528\uff0c\u5728\u8c03\u7528toString\u65b9\u6cd5\u65f6\u4e5f\u4f1a\u4ea7\u751f\u8fd9\u4e2a\u5f02\u5e38\uff09<\/li><li>\u901a\u8fc7 JVM \u542f\u52a8\u53c2\u6570 -Xss \u589e\u52a0\u7ebf\u7a0b\u6808\u5185\u5b58\u7a7a\u95f4\uff0c \u67d0\u4e9b\u6b63\u5e38\u4f7f\u7528\u573a\u666f\u9700\u8981\u6267\u884c\u5927\u91cf\u65b9\u6cd5\u6216\u5305\u542b\u5927\u91cf\u5c40\u90e8\u53d8\u91cf\uff0c\u8fd9\u65f6\u53ef\u4ee5\u9002\u5f53\u5730\u63d0\u9ad8\u7ebf\u7a0b\u6808\u7a7a\u95f4\u9650\u5236<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Java heap space<\/h2>\n\n\n\n<ul class=\"wp-block-list\">null<li>Java \u5806\u7528\u4e8e\u5b58\u50a8\u5bf9\u8c61\u5b9e\u4f8b\uff0c\u6211\u4eec\u53ea\u8981\u4e0d\u65ad\u7684\u521b\u5efa\u5bf9\u8c61\uff0c\u5e76\u4e14\u4fdd\u8bc1 GC Roots \u5230\u5bf9\u8c61\u4e4b\u95f4\u6709\u53ef\u8fbe\u8def\u5f84\u6765\u907f\u514d GC \u6e05\u9664\u8fd9\u4e9b\u5bf9\u8c61\uff0c\u90a3\u968f\u7740\u5bf9\u8c61\u6570\u91cf\u7684\u589e\u52a0\uff0c\u603b\u5bb9\u91cf\u89e6\u53ca\u5806\u7684\u6700\u5927\u5bb9\u91cf\u9650\u5236\u540e\u5c31\u4f1a\u4ea7\u751f\u5185\u5b58\u6ea2\u51fa\u5f02\u5e38\u3002<\/li><li>Java \u5806\u5185\u5b58\u7684 OOM \u5f02\u5e38\u662f\u5b9e\u9645\u5e94\u7528\u4e2d\u6700\u5e38\u89c1\u7684\u5185\u5b58\u6ea2\u51fa\u5f02\u5e38\u3002<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u540c\u6837\u7684\uff0c\u5148\u5199\u4e2a bug\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/**\n * JVM\u53c2\u6570\uff1a-Xmx12m\n *\/\npublic class JavaHeapSpaceDemo {\n    static final int SIZE = 2 * 1024 * 1024;\n    public static void main(String[] a) {\n        int[] i = new int[SIZE];\n    }\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee3\u7801\u8bd5\u56fe\u5206\u914d\u5bb9\u91cf\u4e3a 2M \u7684 int \u6570\u7ec4\uff0c\u5982\u679c\u6307\u5b9a\u542f\u52a8\u53c2\u6570 -Xmx12m\uff0c\u5206\u914d\u5185\u5b58\u5c31\u4e0d\u591f\u7528\uff0c\u5c31\u7c7b\u4f3c\u4e8e\u5c06 XXXL \u53f7\u7684\u5bf9\u8c61\uff0c\u5f80 S \u53f7\u7684 Java heap space \u91cc\u9762\u585e\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>Exception in thread \"main\" java.lang.OutOfMemoryError: Java heap space\n at oom.JavaHeapSpaceDemo.main(JavaHeapSpaceDemo.java:13)<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u5f02\u5e38\u539f\u56e0\u5206\u6790\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u8bf7\u6c42\u521b\u5efa\u4e00\u4e2a\u8d85\u5927\u5bf9\u8c61\uff0c\u901a\u5e38\u662f\u4e00\u4e2a\u5927\u6570\u7ec4<\/li><li>\u8d85\u51fa\u9884\u671f\u7684\u8bbf\u95ee\u91cf\/\u6570\u636e\u91cf\uff0c\u901a\u5e38\u662f\u4e0a\u6e38\u7cfb\u7edf\u8bf7\u6c42\u6d41\u91cf\u98d9\u5347\uff0c\u5e38\u89c1\u4e8e\u5404\u7c7b\u4fc3\u9500\/\u79d2\u6740\u6d3b\u52a8\uff0c\u53ef\u4ee5\u7ed3\u5408\u4e1a\u52a1\u6d41\u91cf\u6307\u6807\u6392\u67e5\u662f\u5426\u6709\u5c16\u72b6\u5cf0\u503c<\/li><li>\u8fc7\u5ea6\u4f7f\u7528\u7ec8\u7ed3\u5668\uff08Finalizer\uff09\uff0c\u8be5\u5bf9\u8c61\u6ca1\u6709\u7acb\u5373\u88ab GC<\/li><li>\u5185\u5b58\u6cc4\u6f0f\uff08Memory Leak\uff09\uff0c\u5927\u91cf\u5bf9\u8c61\u5f15\u7528\u6ca1\u6709\u91ca\u653e\uff0cJVM \u65e0\u6cd5\u5bf9\u5176\u81ea\u52a8\u56de\u6536\uff0c\u5e38\u89c1\u4e8e\u4f7f\u7528\u4e86 File \u7b49\u8d44\u6e90\u6ca1\u6709\u56de\u6536<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u89e3\u51b3\u529e\u6cd5\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u9488\u5bf9\u5927\u90e8\u5206\u60c5\u51b5\uff0c\u901a\u5e38\u53ea\u9700\u8981\u901a\u8fc7 -Xmx \u53c2\u6570\u8c03\u9ad8 JVM \u5806\u5185\u5b58\u7a7a\u95f4\u5373\u53ef\u3002\u5982\u679c\u4ecd\u7136\u6ca1\u6709\u89e3\u51b3\uff0c\u53ef\u4ee5\u53c2\u8003\u4ee5\u4e0b\u60c5\u51b5\u505a\u8fdb\u4e00\u6b65\u5904\u7406\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u5982\u679c\u662f\u8d85\u5927\u5bf9\u8c61\uff0c\u53ef\u4ee5\u68c0\u67e5\u5176\u5408\u7406\u6027\uff0c\u6bd4\u5982\u662f\u5426\u4e00\u6b21\u6027\u67e5\u8be2\u4e86\u6570\u636e\u5e93\u5168\u90e8\u7ed3\u679c\uff0c\u800c\u6ca1\u6709\u505a\u7ed3\u679c\u6570\u9650\u5236<\/li><li>\u5982\u679c\u662f\u4e1a\u52a1\u5cf0\u503c\u538b\u529b\uff0c\u53ef\u4ee5\u8003\u8651\u6dfb\u52a0\u673a\u5668\u8d44\u6e90\uff0c\u6216\u8005\u505a\u9650\u6d41\u964d\u7ea7\u3002<\/li><li>\u5982\u679c\u662f\u5185\u5b58\u6cc4\u6f0f\uff0c\u9700\u8981\u627e\u5230\u6301\u6709\u7684\u5bf9\u8c61\uff0c\u4fee\u6539\u4ee3\u7801\u8bbe\u8ba1\uff0c\u6bd4\u5982\u5173\u95ed\u6ca1\u6709\u91ca\u653e\u7684\u8fde\u63a5<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u770b\u5230\u8fd9\u91cc\uff0c\u4f60\u73b0\u5728\u77e5\u9053\u4e86\u5185\u5b58\u6cc4\u9732\u548c\u5185\u5b58\u6ea2\u51fa\u7684\u533a\u522b\u4e86\u5417\uff1f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5185\u5b58\u6ea2\u51fa(out of memory)\uff0c\u662f\u6307\u7a0b\u5e8f\u5728\u7533\u8bf7\u5185\u5b58\u65f6\uff0c\u6ca1\u6709\u8db3\u591f\u7684\u5185\u5b58\u7a7a\u95f4\u4f9b\u5176\u4f7f\u7528\uff0c\u51fa\u73b0out of memory\uff1b\u6bd4\u5982\u7533\u8bf7\u4e86\u4e00\u4e2a Integer\uff0c\u4f46\u7ed9\u5b83\u5b58\u4e86 Long \u624d\u80fd\u5b58\u4e0b\u7684\u6570\uff0c\u90a3\u5c31\u662f\u5185\u5b58\u6ea2\u51fa\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5185\u5b58\u6cc4\u9732( memory leak)\uff0c\u662f\u6307\u7a0b\u5e8f\u5728\u7533\u8bf7\u5185\u5b58\u540e\uff0c\u65e0\u6cd5\u91ca\u653e\u5df2\u7533\u8bf7\u7684\u5185\u5b58\u7a7a\u95f4\uff0c\u4e00\u6b21\u5185\u5b58\u6cc4\u9732\u5371\u5bb3\u53ef\u4ee5\u5ffd\u7565\uff0c\u4f46\u5185\u5b58\u6cc4\u9732\u5806\u79ef\u540e\u679c\u5f88\u4e25\u91cd\uff0c\u65e0\u8bba\u591a\u5c11\u5185\u5b58\uff0c\u8fdf\u65e9\u4f1a\u88ab\u5360\u5149\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">memory leak \u6700\u7ec8\u4f1a\u5bfc\u81f4 out of memory\uff01<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">GC overhead limit exceeded<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">JVM \u5185\u7f6e\u4e86\u5783\u573e\u56de\u6536\u673a\u5236GC\uff0c\u6240\u4ee5\u4f5c\u4e3a Javaer \u7684\u6211\u4eec\u4e0d\u9700\u8981\u624b\u5de5\u7f16\u5199\u4ee3\u7801\u6765\u8fdb\u884c\u5185\u5b58\u5206\u914d\u548c\u91ca\u653e\uff0c\u4f46\u662f\u5f53 Java \u8fdb\u7a0b\u82b1\u8d39 98% \u4ee5\u4e0a\u7684\u65f6\u95f4\u6267\u884c GC\uff0c\u4f46\u53ea\u6062\u590d\u4e86\u4e0d\u5230 2% \u7684\u5185\u5b58\uff0c\u4e14\u8be5\u52a8\u4f5c\u8fde\u7eed\u91cd\u590d\u4e86 5 \u6b21\uff0c\u5c31\u4f1a\u629b\u51fa java.lang.OutOfMemoryError:GC overhead limit exceeded \u9519\u8bef\uff08\u4fd7\u79f0\uff1a\u5783\u573e\u56de\u6536\u4e0a\u5934\uff09\u3002\u7b80\u5355\u5730\u8bf4\uff0c\u5c31\u662f\u5e94\u7528\u7a0b\u5e8f\u5df2\u7ecf\u57fa\u672c\u8017\u5c3d\u4e86\u6240\u6709\u53ef\u7528\u5185\u5b58\uff0c GC \u4e5f\u65e0\u6cd5\u56de\u6536\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5047\u5982\u4e0d\u629b\u51fa GC overhead limit exceeded \u9519\u8bef\uff0c\u90a3 GC \u6e05\u7406\u7684\u90a3\u4e48\u4e00\u4e22\u4e22\u5185\u5b58\u5f88\u5feb\u5c31\u4f1a\u88ab\u518d\u6b21\u586b\u6ee1\uff0c\u8feb\u4f7f GC \u518d\u6b21\u6267\u884c\uff0c\u8fd9\u6837\u6076\u6027\u5faa\u73af\uff0cCPU \u4f7f\u7528\u7387 100%\uff0c\u800c GC \u6ca1\u4ec0\u4e48\u6548\u679c\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u540c\u6837\u7684\u5148\u5199\u4e2a bug\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u51fa\u73b0\u8fd9\u4e2a\u9519\u8bef\u7684\u5b9e\u4f8b\uff0c\u5176\u5b9e\u6211\u4eec\u5199\u4e2a\u65e0\u9650\u5faa\u73af\uff0c\u5f80 List \u6216 Map \u52a0\u6570\u636e\u5c31\u4f1a\u4e00\u76f4 Full GC\uff0c\u76f4\u5230\u625b\u4e0d\u4f4f\uff0c\u8fd9\u91cc\u7528\u4e00\u4e2a\u4e0d\u5bb9\u6613\u53d1\u73b0\u7684\u6817\u5b50\u3002\u6211\u4eec\u5f80 map \u4e2d\u6dfb\u52a0 1000 \u4e2a\u5143\u7d20\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/**\n * JVM \u53c2\u6570\uff1a -Xmx14m -XX:+PrintGCDetails\n *\/\npublic class KeylessEntry {\n    static class Key {\n        Integer id;\n        Key(Integer id) {\n            this.id = id;\n        }\n        @Override\n        public int hashCode() {\n            return id.hashCode();\n        }\n    }\n    public static void main(String[] args) {\n        Map m = new HashMap();\n        while (true){\n            for (int i = 0; i &lt; 1000; i++){\n                if (!m.containsKey(new Key(i))){\n                    m.put(new Key(i), \"Number:\" + i);\n                }\n            }\n            System.out.println(\"m.size()=\" + m.size());\n        }\n    }\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee3\u7801\u8dd1\u8d77\u6765\uff0c\u4e0d\u4e00\u4f1a\u5c31\u51fa\u73b0\u4e86\u5f02\u5e38\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>...\nm.size()=54000\nm.size()=55000\nm.size()=56000\nException in thread \"main\" java.lang.OutOfMemoryError: GC overhead limit exceeded<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ece\u8f93\u51fa\u7ed3\u679c\u53ef\u4ee5\u770b\u5230\uff0c\u6211\u4eec\u7684\u9650\u5236 1000 \u6761\u6570\u636e\u6ca1\u6709\u8d77\u4f5c\u7528\uff0cmap \u5bb9\u91cf\u8fdc\u8d85\u8fc7\u4e86 1000\uff0c\u800c\u4e14\u6700\u540e\u4e5f\u51fa\u73b0\u4e86\u6211\u4eec\u60f3\u8981\u7684\u9519\u8bef\uff0c\u8fd9\u662f\u56e0\u4e3a\u7c7b Key \u53ea\u91cd\u5199\u4e86 hashCode() \u65b9\u6cd5\uff0c\u5374\u6ca1\u6709\u91cd\u5199 equals() \u65b9\u6cd5\uff0c\u6211\u4eec\u5728\u4f7f\u7528 containsKey() \u65b9\u6cd5\u5176\u5b9e\u5c31\u51fa\u73b0\u4e86\u95ee\u9898\uff0c\u4e8e\u662f\u5c31\u4f1a\u4e00\u76f4\u5f80 HashMap \u4e2d\u6dfb\u52a0 Key\uff0c\u76f4\u81f3 GC \u90fd\u6e05\u7406\u4e0d\u6389\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u770b\u5230\u8fd9\u91cc\uff0c\u6211\u4eec\u5c31\u5e94\u8be5\u8054\u60f3\u5230HashMap\u539f\u7406\u4ee5\u53ca\u4e3a\u4ec0\u4e48\u9700\u8981\u540c\u65f6\u5b9e\u73b0equals\u548chashcode\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6267\u884c\u8fd9\u4e2a\u7a0b\u5e8f\u7684\u6700\u7ec8\u9519\u8bef\uff0c\u548c JVM \u914d\u7f6e\u4e5f\u4f1a\u6709\u5173\u7cfb\uff0c\u5982\u679c\u8bbe\u7f6e\u7684\u5806\u5185\u5b58\u7279\u522b\u5c0f\uff0c\u4f1a\u76f4\u63a5\u62a5 Java heap space\u3002\u7b97\u662f\u88ab\u8fd9\u4e2a\u9519\u8bef\u622a\u80e1\u4e86\uff0c\u6240\u4ee5\u6709\u65f6\uff0c\u5728\u8d44\u6e90\u53d7\u9650\u7684\u60c5\u51b5\u4e0b\uff0c\u65e0\u6cd5\u51c6\u786e\u9884\u6d4b\u7a0b\u5e8f\u4f1a\u6b7b\u4e8e\u54ea\u79cd\u5177\u4f53\u7684\u539f\u56e0\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0b\u9762\u770b\u770b\u89e3\u51b3\u601d\u8def\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u6dfb\u52a0 JVM \u53c2\u6570-XX:-UseGCOverheadLimit \u4e0d\u63a8\u8350\u8fd9\u4e48\u5e72\uff0c\u6ca1\u6709\u771f\u6b63\u89e3\u51b3\u95ee\u9898\uff0c\u53ea\u662f\u5c06\u5f02\u5e38\u63a8\u8fdf<\/li><li>\u68c0\u67e5\u9879\u76ee\u4e2d\u662f\u5426\u6709\u5927\u91cf\u7684\u6b7b\u5faa\u73af\u6216\u6709\u4f7f\u7528\u5927\u5185\u5b58\u7684\u4ee3\u7801\uff0c\u4f18\u5316\u4ee3\u7801<\/li><li>dump\u5185\u5b58\u5206\u6790\uff0c\u68c0\u67e5\u662f\u5426\u5b58\u5728\u5185\u5b58\u6cc4\u9732\uff0c\u5982\u679c\u6ca1\u6709\uff0c\u52a0\u5927\u5185\u5b58<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Direct buffer memory<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4eec\u4f7f\u7528 NIO \u7684\u65f6\u5019\u7ecf\u5e38\u9700\u8981\u4f7f\u7528 ByteBuffer \u6765\u8bfb\u53d6\u6216\u5199\u5165\u6570\u636e\uff0c\u8fd9\u662f\u4e00\u79cd\u57fa\u4e8e Channel(\u901a\u9053) \u548c Buffer(\u7f13\u51b2\u533a)\u7684 I\/O \u65b9\u5f0f\uff0c\u5b83\u53ef\u4ee5\u4f7f\u7528 Native \u51fd\u6570\u5e93\u76f4\u63a5\u5206\u914d\u5806\u5916\u5185\u5b58\uff0c\u7136\u540e\u901a\u8fc7\u4e00\u4e2a\u5b58\u50a8\u5728 Java \u5806\u91cc\u9762\u7684 DirectByteBuffer \u5bf9\u8c61\u4f5c\u4e3a\u8fd9\u5757\u5185\u5b58\u7684\u5f15\u7528\u8fdb\u884c\u64cd\u4f5c\u3002\u8fd9\u6837\u5728\u4e00\u4e9b\u573a\u666f\u5c31\u907f\u514d\u4e86 Java \u5806\u548c Native \u4e2d\u6765\u56de\u590d\u5236\u6570\u636e\uff0c\u6240\u4ee5\u6027\u80fd\u4f1a\u6709\u6240\u63d0\u9ad8\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Java \u5141\u8bb8\u5e94\u7528\u7a0b\u5e8f\u901a\u8fc7 Direct ByteBuffer \u76f4\u63a5\u8bbf\u95ee\u5806\u5916\u5185\u5b58\uff0c\u8bb8\u591a\u9ad8\u6027\u80fd\u7a0b\u5e8f\u901a\u8fc7 Direct ByteBuffer \u7ed3\u5408\u5185\u5b58\u6620\u5c04\u6587\u4ef6\uff08Memory Mapped File\uff09\u5b9e\u73b0\u9ad8\u901f IO\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8001\u89c4\u77e9\uff0c\u5148\u5199\u4e2a bug\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>ByteBuffer.allocate(capability) \u662f\u5206\u914d JVM \u5806\u5185\u5b58\uff0c\u5c5e\u4e8e GC \u7ba1\u8f96\u8303\u56f4\uff0c\u9700\u8981\u5185\u5b58\u62f7\u8d1d\u6240\u4ee5\u901f\u5ea6\u76f8\u5bf9\u8f83\u6162\uff1b<\/li><li>ByteBuffer.allocateDirect(capability) \u662f\u5206\u914d OS \u672c\u5730\u5185\u5b58\uff0c\u4e0d\u5c5e\u4e8e GC \u7ba1\u8f96\u8303\u56f4\uff0c\u7531\u4e8e\u4e0d\u9700\u8981\u5185\u5b58\u62f7\u8d1d\u6240\u4ee5\u901f\u5ea6\u76f8\u5bf9\u8f83\u5feb\uff1b<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u679c\u4e0d\u65ad\u5206\u914d\u672c\u5730\u5185\u5b58\uff0c\u5806\u5185\u5b58\u5f88\u5c11\u4f7f\u7528\uff0c\u90a3\u4e48 JVM \u5c31\u4e0d\u9700\u8981\u6267\u884c GC\uff0cDirectByteBuffer \u5bf9\u8c61\u5c31\u4e0d\u4f1a\u88ab\u56de\u6536\uff0c\u8fd9\u65f6\u867d\u7136\u5806\u5185\u5b58\u5145\u8db3\uff0c\u4f46\u672c\u5730\u5185\u5b58\u53ef\u80fd\u5df2\u7ecf\u4e0d\u591f\u7528\u4e86\uff0c\u5c31\u4f1a\u51fa\u73b0 OOM\uff0c\u672c\u5730\u76f4\u63a5\u5185\u5b58\u6ea2\u51fa\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/**\n *  VM Options\uff1a-Xms10m,-Xmx10m,-XX:+PrintGCDetails -XX:MaxDirectMemorySize=5m\n *\/\npublic class DirectBufferMemoryDemo {\n    public static void main(String[] args) {\n        System.out.println(\"maxDirectMemory is:\"+sun.misc.VM.maxDirectMemory() \/ 1024 \/ 1024 + \"MB\");\n        \/\/ByteBuffer buffer = ByteBuffer.allocate(6*1024*1024);\n        ByteBuffer buffer = ByteBuffer.allocateDirect(6*1024*1024);\n    }\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u6700\u5927\u76f4\u63a5\u5185\u5b58\uff0c\u9ed8\u8ba4\u662f\u7535\u8111\u5185\u5b58\u7684 1\/4\uff0c\u6240\u4ee5\u6211\u4eec\u8bbe\u5c0f\u70b9\uff0c\u7136\u540e\u4f7f\u7528\u76f4\u63a5\u5185\u5b58\u8d85\u8fc7\u8fd9\u4e2a\u503c\uff0c\u5c31\u4f1a\u51fa\u73b0 OOM\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>maxDirectMemory is:5MB\nException in thread \"main\" java.lang.OutOfMemoryError: Direct buffer memory<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u89e3\u51b3\u65b9\u6848<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Java \u53ea\u80fd\u901a\u8fc7 ByteBuffer.allocateDirect \u65b9\u6cd5\u4f7f\u7528 Direct ByteBuffer\uff0c\u56e0\u6b64\uff0c\u53ef\u4ee5\u901a\u8fc7 Arthas \u7b49\u5728\u7ebf\u8bca\u65ad\u5de5\u5177\u62e6\u622a\u8be5\u65b9\u6cd5\u8fdb\u884c\u6392\u67e5<\/li><li>\u68c0\u67e5\u662f\u5426\u76f4\u63a5\u6216\u95f4\u63a5\u4f7f\u7528\u4e86 NIO\uff0c\u5982 netty\uff0cjetty \u7b49<\/li><li>\u901a\u8fc7\u542f\u52a8\u53c2\u6570 -XX:MaxDirectMemorySize \u8c03\u6574 Direct ByteBuffer \u7684\u4e0a\u9650\u503c<\/li><li>\u68c0\u67e5 JVM \u53c2\u6570\u662f\u5426\u6709 -XX:+DisableExplicitGC \u9009\u9879\uff0c\u5982\u679c\u6709\u5c31\u53bb\u6389\uff0c\u56e0\u4e3a\u8be5\u53c2\u6570\u4f1a\u4f7f System.gc() \u5931\u6548<\/li><li>\u68c0\u67e5\u5806\u5916\u5185\u5b58\u4f7f\u7528\u4ee3\u7801\uff0c\u786e\u8ba4\u662f\u5426\u5b58\u5728\u5185\u5b58\u6cc4\u6f0f\uff1b\u6216\u8005\u901a\u8fc7\u53cd\u5c04\u8c03\u7528 sun.misc.Cleaner \u7684 clean() \u65b9\u6cd5\u6765\u4e3b\u52a8\u91ca\u653e\u88ab Direct ByteBuffer \u6301\u6709\u7684\u5185\u5b58\u7a7a\u95f4<\/li><li>\u5185\u5b58\u5bb9\u91cf\u786e\u5b9e\u4e0d\u8db3\uff0c\u5347\u7ea7\u914d\u7f6e<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Unable to create new native thread<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6bcf\u4e2a Java \u7ebf\u7a0b\u90fd\u9700\u8981\u5360\u7528\u4e00\u5b9a\u7684\u5185\u5b58\u7a7a\u95f4\uff0c\u5f53 JVM \u5411\u5e95\u5c42\u64cd\u4f5c\u7cfb\u7edf\u8bf7\u6c42\u521b\u5efa\u4e00\u4e2a\u65b0\u7684 native \u7ebf\u7a0b\u65f6\uff0c\u5982\u679c\u6ca1\u6709\u8db3\u591f\u7684\u8d44\u6e90\u5206\u914d\u5c31\u4f1a\u62a5\u6b64\u7c7b\u9519\u8bef\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>public static void main(String[] args) {\n  while(true){\n    new Thread(() -&gt; {\n      try {\n        Thread.sleep(Integer.MAX_VALUE);\n      } catch(InterruptedException e) { }\n    }).start();\n  }\n}<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>Error occurred during initialization of VM\njava.lang.OutOfMemoryError: unable to create new native thread<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u539f\u56e0\u5206\u6790\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/gitee.com\/xmtblog\/img\/raw\/master\/2020\/oom2.png\" alt=\"\" \/><figcaption>OutOfMemoryError \u539f\u56e0\u5206\u6790<\/figcaption><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">JVM \u5411 OS \u8bf7\u6c42\u521b\u5efa native \u7ebf\u7a0b\u5931\u8d25\uff0c\u5c31\u4f1a\u629b\u51fa Unableto createnewnativethread\uff0c\u5e38\u89c1\u7684\u539f\u56e0\u5305\u62ec\u4ee5\u4e0b\u51e0\u7c7b\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u7ebf\u7a0b\u6570\u8d85\u8fc7\u64cd\u4f5c\u7cfb\u7edf\u6700\u5927\u7ebf\u7a0b\u6570\u9650\u5236\uff08\u548c\u5e73\u53f0\u6709\u5173\uff09<\/li><li>\u7ebf\u7a0b\u6570\u8d85\u8fc7 kernel.pid_max\uff08\u53ea\u80fd\u91cd\u542f\uff09<\/li><li>native \u5185\u5b58\u4e0d\u8db3\uff1b\u8be5\u95ee\u9898\u53d1\u751f\u7684\u5e38\u89c1\u8fc7\u7a0b\u4e3b\u8981\u5305\u62ec\u4ee5\u4e0b\u51e0\u6b65\uff1a<\/li><\/ul>\n\n\n\n<ol class=\"wp-block-list\"><li>JVM \u5185\u90e8\u7684\u5e94\u7528\u7a0b\u5e8f\u8bf7\u6c42\u521b\u5efa\u4e00\u4e2a\u65b0\u7684 Java \u7ebf\u7a0b\uff1b<\/li><li>JVM native \u65b9\u6cd5\u4ee3\u7406\u4e86\u8be5\u6b21\u8bf7\u6c42\uff0c\u5e76\u5411\u64cd\u4f5c\u7cfb\u7edf\u8bf7\u6c42\u521b\u5efa\u4e00\u4e2a native \u7ebf\u7a0b\uff1b<\/li><li>\u64cd\u4f5c\u7cfb\u7edf\u5c1d\u8bd5\u521b\u5efa\u4e00\u4e2a\u65b0\u7684 native \u7ebf\u7a0b\uff0c\u5e76\u4e3a\u5176\u5206\u914d\u5185\u5b58\uff1b<\/li><li>\u5982\u679c\u64cd\u4f5c\u7cfb\u7edf\u7684\u865a\u62df\u5185\u5b58\u5df2\u8017\u5c3d\uff0c\u6216\u662f\u53d7\u5230 32 \u4f4d\u8fdb\u7a0b\u7684\u5730\u5740\u7a7a\u95f4\u9650\u5236\uff0c\u64cd\u4f5c\u7cfb\u7edf\u5c31\u4f1a\u62d2\u7edd\u672c\u6b21 native \u5185\u5b58\u5206\u914d\uff1b<\/li><li>JVM \u5c06\u629b\u51fa java.lang.OutOfMemoryError:Unableto createnewnativethread \u9519\u8bef\u3002<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">\u89e3\u51b3\u65b9\u6848\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u60f3\u529e\u6cd5\u964d\u4f4e\u7a0b\u5e8f\u4e2d\u521b\u5efa\u7ebf\u7a0b\u7684\u6570\u91cf\uff0c\u5206\u6790\u5e94\u7528\u662f\u5426\u771f\u7684\u9700\u8981\u521b\u5efa\u8fd9\u4e48\u591a\u7ebf\u7a0b<\/li><li>\u5982\u679c\u786e\u5b9e\u9700\u8981\u521b\u5efa\u5f88\u591a\u7ebf\u7a0b\uff0c\u8c03\u9ad8 OS \u5c42\u9762\u7684\u7ebf\u7a0b\u6700\u5927\u6570\uff1a\u6267\u884c ulimia-a \u67e5\u770b\u6700\u5927\u7ebf\u7a0b\u6570\u9650\u5236\uff0c\u4f7f\u7528 ulimit-u xxx \u8c03\u6574\u6700\u5927\u7ebf\u7a0b\u6570\u9650\u5236<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">OutOfMemoryError&#8211;&gt;Metaspace<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">JDK 1.8 \u4e4b\u524d\u4f1a\u51fa\u73b0 Permgen space\uff0c\u8be5\u9519\u8bef\u8868\u793a\u6c38\u4e45\u4ee3\uff08Permanent Generation\uff09\u5df2\u7528\u6ee1\uff0c\u901a\u5e38\u662f\u56e0\u4e3a\u52a0\u8f7d\u7684 class \u6570\u76ee\u592a\u591a\u6216\u4f53\u79ef\u592a\u5927\u3002\u968f\u7740 1.8 \u4e2d\u6c38\u4e45\u4ee3\u7684\u53d6\u6d88\uff0c\u5c31\u4e0d\u4f1a\u51fa\u73b0\u8fd9\u79cd\u5f02\u5e38\u4e86\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Metaspace \u662f\u65b9\u6cd5\u533a\u5728 HotSpot \u4e2d\u7684\u5b9e\u73b0\uff0c\u5b83\u4e0e\u6c38\u4e45\u4ee3\u6700\u5927\u7684\u533a\u522b\u5728\u4e8e\uff0c\u5143\u7a7a\u95f4\u5e76\u4e0d\u5728\u865a\u62df\u673a\u5185\u5b58\u4e2d\u800c\u662f\u4f7f\u7528\u672c\u5730\u5185\u5b58\uff0c\u4f46\u662f\u672c\u5730\u5185\u5b58\u4e5f\u6709\u6253\u6ee1\u7684\u65f6\u5019\uff0c\u6240\u4ee5\u4e5f\u4f1a\u6709\u5f02\u5e38\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5199\u4e2a bug\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/**\n * JVM Options: -XX:MetaspaceSize=10m -XX:MaxMetaspaceSize=10m\n *\/\npublic class MetaspaceOOMDemo {\n    public static void main(String[] args) {\n        while (true) {\n            Enhancer enhancer = new Enhancer();\n            enhancer.setSuperclass(MetaspaceOOMDemo.class);\n            enhancer.setUseCache(false);\n            enhancer.setCallback((MethodInterceptor) (o, method, objects, methodProxy) -&gt; {\n                \/\/\u52a8\u6001\u4ee3\u7406\u521b\u5efa\u5bf9\u8c61\n                return methodProxy.invokeSuper(o, objects);\n            });\n            enhancer.create();\n        }\n    }\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u501f\u52a9 Spring \u7684 GCLib \u5b9e\u73b0\u52a8\u6001\u521b\u5efa\u5bf9\u8c61\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>Exception in thread \"main\" org.springframework.cglib.core.CodeGenerationException: java.lang.OutOfMemoryError--&gt;Metaspace<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u89e3\u51b3\u65b9\u6848\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u65b9\u6cd5\u533a\u6ea2\u51fa\u4e5f\u662f\u4e00\u79cd\u5e38\u89c1\u7684\u5185\u5b58\u6ea2\u51fa\u5f02\u5e38\uff0c\u5728\u7ecf\u5e38\u8fd0\u884c\u65f6\u751f\u6210\u5927\u91cf\u52a8\u6001\u7c7b\u7684\u5e94\u7528\u573a\u666f\u4e2d\uff0c\u5c31\u5e94\u8be5\u7279\u522b\u5173\u6ce8\u8fd9\u4e9b\u7c7b\u7684\u56de\u6536\u60c5\u51b5\u3002\u8fd9\u7c7b\u573a\u666f\u9664\u4e86\u4e0a\u8fb9\u7684 GCLib \u5b57\u8282\u7801\u589e\u5f3a\u548c\u52a8\u6001\u8bed\u8a00\u5916\uff0c\u5e38\u89c1\u7684\u8fd8\u6709\uff0c\u5927\u91cf JSP \u6216\u52a8\u6001\u4ea7\u751f JSP  \u6587\u4ef6\u7684\u5e94\u7528\uff08\u8fdc\u53e4\u65f6\u4ee3\u7684\u4f20\u7edf\u8f6f\u4ef6\u884c\u4e1a\u53ef\u80fd\u4f1a\u6709\uff09\u3001\u57fa\u4e8e OSGi \u7684\u5e94\u7528\uff08\u5373\u4f7f\u540c\u4e00\u4e2a\u7c7b\u6587\u4ef6\uff0c\u88ab\u4e0d\u540c\u7684\u52a0\u8f7d\u5668\u52a0\u8f7d\u4e5f\u4f1a\u89c6\u4e3a\u4e0d\u540c\u7684\u7c7b\uff09\u7b49\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u65b9\u6cd5\u533a\u5728 JDK8 \u4e2d\u4e00\u822c\u4e0d\u592a\u5bb9\u6613\u4ea7\u751f\uff0cHotSpot \u63d0\u4f9b\u4e86\u4e00\u4e9b\u53c2\u6570\u6765\u8bbe\u7f6e\u5143\u7a7a\u95f4\uff0c\u53ef\u4ee5\u8d77\u5230\u9884\u9632\u4f5c\u7528\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>-XX:MaxMetaspaceSize \u8bbe\u7f6e\u5143\u7a7a\u95f4\u6700\u5927\u503c\uff0c\u9ed8\u8ba4\u662f -1\uff0c\u8868\u793a\u4e0d\u9650\u5236\uff08\u8fd8\u662f\u8981\u53d7\u672c\u5730\u5185\u5b58\u5927\u5c0f\u9650\u5236\u7684\uff09<\/li><li>-XX:MetaspaceSize \u6307\u5b9a\u5143\u7a7a\u95f4\u7684\u521d\u59cb\u7a7a\u95f4\u5927\u5c0f\uff0c\u4ee5\u5b57\u8282\u4e3a\u5355\u4f4d\uff0c\u8fbe\u5230\u8be5\u503c\u5c31\u4f1a\u89e6\u53d1 GC \u8fdb\u884c\u7c7b\u578b\u5378\u8f7d\uff0c\u540c\u65f6\u6536\u96c6\u5668\u4f1a\u5bf9\u8be5\u503c\u8fdb\u884c\u8c03\u6574<\/li><li>-XX:MinMetaspaceFreeRatio \u5728 GC \u4e4b\u540e\u63a7\u5236\u6700\u5c0f\u7684\u5143\u7a7a\u95f4\u5269\u4f59\u5bb9\u91cf\u7684\u767e\u5206\u6bd4\uff0c\u53ef\u51cf\u5c11\u56e0\u5143\u7a7a\u95f4\u4e0d\u8db3\u5bfc\u81f4\u7684\u5783\u573e\u6536\u96c6\u9891\u7387\uff0c\u7c7b\u4f3c\u7684\u8fd8\u6709 MaxMetaspaceFreeRatio<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Requested array size exceeds VM limit<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd8\u662f\u5148\u5199 Bug\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>public static void main(String[] args) {\n  int[] arr = new int[Integer.MAX_VALUE];\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u4e2a\u6bd4\u8f83\u7b80\u5355\uff0c\u5efa\u4e2a\u8d85\u7ea7\u5927\u6570\u7ec4\u5c31\u4f1a\u51fa\u73b0 OOM\uff0c\u4e0d\u591a\u8bf4\u4e86<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>Exception in thread \"main\" java.lang.OutOfMemoryError: Requested array size exceeds VM limit<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">JVM \u9650\u5236\u4e86\u6570\u7ec4\u7684\u6700\u5927\u957f\u5ea6\uff0c\u8be5\u9519\u8bef\u8868\u793a\u7a0b\u5e8f\u8bf7\u6c42\u521b\u5efa\u7684\u6570\u7ec4\u8d85\u8fc7\u6700\u5927\u957f\u5ea6\u9650\u5236\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">JVM \u5728\u4e3a\u6570\u7ec4\u5206\u914d\u5185\u5b58\u524d\uff0c\u4f1a\u68c0\u67e5\u8981\u5206\u914d\u7684\u6570\u636e\u7ed3\u6784\u5728\u7cfb\u7edf\u4e2d\u662f\u5426\u53ef\u5bfb\u5740\uff0c\u901a\u5e38\u4e3a Integer.MAX_VALUE-2\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6b64\u7c7b\u95ee\u9898\u6bd4\u8f83\u7f55\u89c1\uff0c\u901a\u5e38\u9700\u8981\u68c0\u67e5\u4ee3\u7801\uff0c\u786e\u8ba4\u4e1a\u52a1\u662f\u5426\u9700\u8981\u521b\u5efa\u5982\u6b64\u5927\u7684\u6570\u7ec4\uff0c\u662f\u5426\u53ef\u4ee5\u62c6\u5206\u4e3a\u591a\u4e2a\u5757\uff0c\u5206\u6279\u6267\u884c\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Out of swap space<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u542f\u52a8 Java \u5e94\u7528\u7a0b\u5e8f\u4f1a\u5206\u914d\u6709\u9650\u7684\u5185\u5b58\u3002\u6b64\u9650\u5236\u662f\u901a\u8fc7-Xmx\u548c\u5176\u4ed6\u7c7b\u4f3c\u7684\u542f\u52a8\u53c2\u6570\u6307\u5b9a\u7684\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728 JVM \u8bf7\u6c42\u7684\u603b\u5185\u5b58\u5927\u4e8e\u53ef\u7528\u7269\u7406\u5185\u5b58\u7684\u60c5\u51b5\u4e0b\uff0c\u64cd\u4f5c\u7cfb\u7edf\u5f00\u59cb\u5c06\u5185\u5bb9\u4ece\u5185\u5b58\u6362\u51fa\u5230\u786c\u76d8\u9a71\u52a8\u5668\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/gitee.com\/xmtblog\/img\/raw\/master\/2020\/oom3.png\" alt=\"\" \/><figcaption>Out of swap space<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u8be5\u9519\u8bef\u8868\u793a\u6240\u6709\u53ef\u7528\u7684\u865a\u62df\u5185\u5b58\u5df2\u88ab\u8017\u5c3d\u3002\u865a\u62df\u5185\u5b58\uff08Virtual Memory\uff09\u7531\u7269\u7406\u5185\u5b58\uff08Physical Memory\uff09\u548c\u4ea4\u6362\u7a7a\u95f4\uff08Swap Space\uff09\u4e24\u90e8\u5206\u7ec4\u6210\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Kill process or sacrifice child<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u64cd\u4f5c\u7cfb\u7edf\u662f\u5efa\u7acb\u5728\u6d41\u7a0b\u6982\u5ff5\u4e4b\u4e0a\u7684\u3002\u8fd9\u4e9b\u8fdb\u7a0b\u7531\u51e0\u4e2a\u5185\u6838\u4f5c\u4e1a\u8d1f\u8d23\uff0c\u5176\u4e2d\u4e00\u4e2a\u540d\u4e3a\u201c Out of memory Killer\u201d\uff0c\u5b83\u4f1a\u5728\u53ef\u7528\u5185\u5b58\u6781\u4f4e\u7684\u60c5\u51b5\u4e0b\u201c\u6740\u6b7b\u201d\uff08kill\uff09\u67d0\u4e9b\u8fdb\u7a0b\u3002OOM Killer \u4f1a\u5bf9\u6240\u6709\u8fdb\u7a0b\u8fdb\u884c\u6253\u5206\uff0c\u7136\u540e\u5c06\u8bc4\u5206\u8f83\u4f4e\u7684\u8fdb\u7a0b\u201c\u6740\u6b7b\u201d\uff0c\u5177\u4f53\u7684\u8bc4\u5206\u89c4\u5219\u53ef\u4ee5\u53c2\u8003 Surviving the Linux OOM Killer\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0d\u540c\u4e8e\u5176\u4ed6\u7684 OOM \u9519\u8bef\uff0c Killprocessorsacrifice child \u9519\u8bef\u4e0d\u662f\u7531 JVM \u5c42\u9762\u89e6\u53d1\u7684\uff0c\u800c\u662f\u7531\u64cd\u4f5c\u7cfb\u7edf\u5c42\u9762\u89e6\u53d1\u7684\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u539f\u56e0\u5206\u6790<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0cLinux \u5185\u6838\u5141\u8bb8\u8fdb\u7a0b\u7533\u8bf7\u7684\u5185\u5b58\u603b\u91cf\u5927\u4e8e\u7cfb\u7edf\u53ef\u7528\u5185\u5b58\uff0c\u901a\u8fc7\u8fd9\u79cd\u201c\u9519\u5cf0\u590d\u7528\u201d\u7684\u65b9\u5f0f\u53ef\u4ee5\u66f4\u6709\u6548\u7684\u5229\u7528\u7cfb\u7edf\u8d44\u6e90\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7136\u800c\uff0c\u8fd9\u79cd\u65b9\u5f0f\u4e5f\u4f1a\u65e0\u53ef\u907f\u514d\u5730\u5e26\u6765\u4e00\u5b9a\u7684\u201c\u8d85\u5356\u201d\u98ce\u9669\u3002\u4f8b\u5982\u67d0\u4e9b\u8fdb\u7a0b\u6301\u7eed\u5360\u7528\u7cfb\u7edf\u5185\u5b58\uff0c\u7136\u540e\u5bfc\u81f4\u5176\u4ed6\u8fdb\u7a0b\u6ca1\u6709\u53ef\u7528\u5185\u5b58\u3002\u6b64\u65f6\uff0c\u7cfb\u7edf\u5c06\u81ea\u52a8\u6fc0\u6d3b OOM Killer\uff0c\u5bfb\u627e\u8bc4\u5206\u4f4e\u7684\u8fdb\u7a0b\uff0c\u5e76\u5c06\u5176\u201c\u6740\u6b7b\u201d\uff0c\u91ca\u653e\u5185\u5b58\u8d44\u6e90\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u89e3\u51b3\u65b9\u6848<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u5347\u7ea7\u670d\u52a1\u5668\u914d\u7f6e\/\u9694\u79bb\u90e8\u7f72\uff0c\u907f\u514d\u4e89\u7528<\/li><li>OOM Killer \u8c03\u4f18\u3002<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u6700\u540e\u9644\u4e0a\u4e00\u5f20\u201c\u6daf\u6d77\u201d\u5927\u795e\u7684\u56fe\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/gitee.com\/xmtblog\/img\/raw\/master\/2020\/oom4.png\" alt=\"\" \/><figcaption>Java\u5185\u5b58\u6a21\u578b&amp;OOM\u9519\u8bef<\/figcaption><\/figure><\/div>\n\n\n\n<h2 class=\"wp-block-heading\">\u53c2\u8003\u8d44\u6599<\/h2>\n\n\n\n<ul class=\"wp-block-list\"><li><a rel=\"noreferrer noopener\" aria-label=\"\uff08\u5728\u65b0\u7a97\u53e3\u6253\u5f00\uff09\" href=\"https:\/\/plumbr.io\/outofmemoryerror\" target=\"_blank\">https:\/\/plumbr.io\/outofmemoryerror<\/a><\/li><li><a rel=\"noreferrer noopener\" aria-label=\"https:\/\/yq.aliyun.com\/articles\/711191\uff08\u5728\u65b0\u7a97\u53e3\u6253\u5f00\uff09\" href=\"https:\/\/yq.aliyun.com\/articles\/711191\" target=\"_blank\">https:\/\/yq.aliyun.com\/articles\/711191<\/a><\/li><li><a rel=\"noreferrer noopener\" aria-label=\"https:\/\/github.com\/StabilityMan\/StabilityGuide\/blob\/master\/docs\/diagnosis\/jvm\/exception\uff08\u5728\u65b0\u7a97\u53e3\u6253\u5f00\uff09\" href=\"https:\/\/github.com\/StabilityMan\/StabilityGuide\/blob\/master\/docs\/diagnosis\/jvm\/exception\" target=\"_blank\">https:\/\/github.com\/StabilityMan\/StabilityGuide\/blob\/master\/docs\/diagnosis\/jvm\/exception<\/a><\/li><li><a href=\"https:\/\/mp.weixin.qq.com\/s\/gIJvtd8rrZz6ttaoGLddLg\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"https:\/\/mp.weixin.qq.com\/s\/gIJvtd8rrZz6ttaoGLddLg\uff08\u5728\u65b0\u7a97\u53e3\u6253\u5f00\uff09\">https:\/\/mp.weixin.qq.com\/s\/gIJvtd8rrZz6ttaoGLddLg<\/a><\/li><\/ul>\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=5059\">8 \u5e38\u89c1\u7684 OOM \u4ee3\u7801\u548c\u5f02\u5e38\u5206\u6790<\/a><\/p><!-- <div class=\"bd-reward-stl\"><button id=\"bdRewardBtn\"><span><\/span><\/button><\/div> -->","protected":false},"excerpt":{"rendered":"<p>\u5728\u300aJava\u865a\u62df\u673a\u89c4\u8303\u300b\u7684\u89c4\u5b9a\u91cc\uff0c\u9664\u4e86\u7a0b\u5e8f\u8ba1\u6570\u5668\u5916\uff0c\u865a\u62df\u673a\u5185\u5b58\u7684\u5176\u4ed6\u51e0\u4e2a\u8fd0\u884c\u65f6\u533a\u57df\u90fd\u6709\u53d1\u751f OutOfMemo [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[705,1698,601,602,704],"class_list":["post-5059","post","type-post","status-publish","format-standard","hentry","category-java","tag-kernel-space","tag-oom","tag-outofmemoryerror","tag-stackoverflowerror","tag-user-space"],"_links":{"self":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/5059","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=5059"}],"version-history":[{"count":1,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/5059\/revisions"}],"predecessor-version":[{"id":5060,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/5059\/revisions\/5060"}],"wp:attachment":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5059"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5059"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5059"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}