\u4e0d\u8fc7\uff0cJava\u5e76\u4e0d\u91c7\u7528\u5f15\u7528\u8ba1\u6570\u6cd5\u6765\u8fdb\u884c\u5783\u573e\u56de\u6536\uff0c\u56e0\u4e3a\u5b83\u5b58\u5728\u5faa\u73af\u5f15\u7528\u7684\u95ee\u9898\u3002\u5728\u5faa\u73af\u5f15\u7528\u4e2d\uff0c\u4e24\u4e2a\u6216\u591a\u4e2a\u5bf9\u8c61\u76f8\u4e92\u5f15\u7528\uff0c\u4f46\u5b83\u4eec\u53ef\u80fd\u90fd\u5df2\u7ecf\u4e0d\u518d\u88ab\u5176\u4ed6\u6d3b\u52a8\u90e8\u5206\u7684\u5e94\u7528\u7a0b\u5e8f\u6240\u5f15\u7528\u3002\u7531\u4e8e\u5b83\u4eec\u76f8\u4e91\u5f15\u7528\uff0c\u56e0\u6b64\u5b83\u4eec\u7684\u5f15\u7528\u8ba1\u6570\u6c38\u8fdc\u4e0d\u4f1a\u8fbe\u52300\uff0c\u5bfc\u81f4\u5185\u5b58\u6cc4\u6f0f\u3002<\/p>\n
public class ReferenceCounting {
Object instance = null;<\/p>\n
public static void main(String[] args) {
ReferenceCounting objA = new ReferenceCounting();
ReferenceCounting objB = new ReferenceCounting();<\/p>\n
\/\/ \u521b\u5efa\u5faa\u73af\u5f15\u7528
objA.instance = objB;
objB.instance = objA;<\/p>\n
\/\/ \u5c1d\u8bd5\u624b\u52a8\u7f6e\u7a7a\u4ee5\u65ad\u5f00\u5f15\u7528
objA = null;
objB = null;<\/p>\n
\/\/ \u5e0c\u671bGC\u80fd\u56de\u6536objA\u548cobjB\uff0c\u4f46\u5982\u679c\u662f\u91c7\u7528\u5f15\u7528\u8ba1\u6570\u6cd5\uff0c\u5219\u65e0\u6cd5\u56de\u6536
System.gc();
}
}<\/p>\n<\/li>\n
\u5728Java\u4e2d\uff0c\u53ef\u4f5c\u4e3aGC Roots\u7684\u5e38\u89c1\u5bf9\u8c61\u5305\u62ec\uff1a<\/p>\n
\u865a\u62df\u673a\u6808\uff08\u6808\u5e27\u4e2d\u7684\u5c40\u90e8\u53d8\u91cf\u8868\uff09\u4e2d\u5f15\u7528\u7684\u5bf9\u8c61\uff1a\u4f8b\u5982\uff0c\u6b63\u5728\u6267\u884c\u7684\u65b9\u6cd5\u4e2d\u7684\u5c40\u90e8\u53d8\u91cf\u6216\u53c2\u6570\u3002
\u65b9\u6cd5\u533a\u4e2d\u7c7b\u9759\u6001\u5c5e\u6027\u5f15\u7528\u7684\u5bf9\u8c61\uff1a\u8fd9\u4e9b\u9759\u6001\u53d8\u91cf\u6240\u5f15\u7528\u7684\u5bf9\u8c61\u4e5f\u88ab\u79f0\u4e3a GC Roots\u3002
\u65b9\u6cd5\u533a\u4e2d\u5e38\u91cf\u5f15\u7528\u7684\u5bf9\u8c61\uff1a\u4f8b\u5982\uff0c\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\uff08String Table\uff09\u7684\u5f15\u7528
\u672c\u5730\u65b9\u6cd5\u6808\u4e2dJNI\uff08Java Native Interface\uff09\u5f15\u7528\u7684\u5bf9\u8c61\uff1a\u5728\u4f7f\u7528 JNI \u8c03\u7528\u672c\u5730\u65b9\u6cd5\u7684\u8fc7\u7a0b\u4e2d\uff0c\u4f1a\u6d89\u53ca\u5230\u672c\u5730\u65b9\u6cd5\u6808\uff0c\u5176\u4e2d\u5f15\u7528\u7684\u5bf9\u8c61\u4e5f\u662f GC Roots\u3002
\u4e3e\u4e00\u4e2a\u7b80\u5355\u7684\u4f8b\u5b50\u6765\u63cf\u8ff0\u53ef\u8fbe\u6027\u5206\u6790\uff1a<\/p>\n
public class ReachabilityAnalysis {
public static void main(String[] args) {
ReachabilityAnalysis obj = new ReachabilityAnalysis(); \/\/ \u5bf9\u8c61obj\u662f\u53ef\u8fbe\u7684\uff0c\u56e0\u4e3a\u5b83\u88ab\u6808\u4e0a\u7684\u5f15\u7528\u53d8\u91cf\u6240\u5f15\u7528<\/p>\n
\/\/ \u73b0\u5728\u8ba9\u6211\u4eec\u65ad\u5f00\u8fd9\u4e2a\u5f15\u7528
obj = null; \/\/ \u6b64\u65f6\u5bf9\u8c61\u4e0d\u518d\u53ef\u8fbe<\/p>\n
\/\/ \u5783\u573e\u56de\u6536\u53ef\u4ee5\u6267\u884c\u4e86\uff0c\u5b83\u5c06\u4f7f\u7528\u53ef\u8fbe\u6027\u5206\u6790\u6765\u786e\u5b9aobj\u7684\u5185\u5b58\u662f\u5426\u53ef\u4ee5\u88ab\u91ca\u653e
System.gc();
}
}<\/p>\n
\u5728JVM\u6a21\u578b\u4e2d\uff0c\u5783\u573e\u56de\u6536\u4e3b\u8981\u53d1\u751f\u5728\u5806\u5185\u5b58\uff08Heap\uff09\u4e2d\uff0c\u56e0\u4e3a\u8fd9\u91cc\u662f\u5b58\u653e\u5bf9\u8c61\u5b9e\u4f8b\u7684\u5730\u65b9\u3002\u5f53\u524d\u4e3b\u6d41\u7684JVM\u4f7f\u7528\u5206\u4ee3\u5783\u573e\u6536\u96c6\u7b97\u6cd5\uff0c\u5c06\u5806\u5185\u5b58\u5206\u4e3a\u5e74\u8f7b\u4ee3\uff08Young Generation\uff09\uff0c\u8001\u5e74\u4ee3\uff08Old Generation\uff09\uff0c\u4ee5\u53ca\u6c38\u4e45\u4ee3\uff08Permanent Generation\uff0c\u4f46\u5728Java 8\u53ca\u4e4b\u540e\u88abMetaSpace\u6240\u66ff\u4ee3\uff09\u3002\u4e0d\u540c\u4ee3\u7684\u5bf9\u8c61\u4f1a\u6839\u636e\u5176\u751f\u547d\u5468\u671f\u7684\u4e0d\u540c\u88ab\u76f8\u5e94\u7684\u5783\u573e\u56de\u6536\u5668\u56de\u6536\uff0c\u4ee5\u63d0\u9ad8\u56de\u6536\u6548\u7387\u3002<\/p>\n
\u5783\u573e\u56de\u6536\u7b97\u6cd5\u3001\u5783\u573e\u56de\u6536\u5668\u7684\u9009\u62e9\u4ee5\u53ca\u5783\u573e\u56de\u6536\u7684\u65f6\u673a\uff0c\u901a\u5e38\u662f\u7531JVM\u81ea\u52a8\u7ba1\u7406\u7684\uff0c\u4f46\u662f\u5f00\u53d1\u8005\u53ef\u4ee5\u901a\u8fc7JVM\u53c2\u6570\u6765\u5bf9\u5176\u8fdb\u884c\u8c03\u4f18\u3002<\/p>\n<\/li>\n<\/ol>\n\n\n
\n\n\n
\u5783\u573e\u56de\u6536\u7b97\u6cd5<\/h2>\n\n- \u6807\u8bb0-\u6e05\u9664\u7b97\u6cd5\n
\u6807\u8bb0\u9636\u6bb5\uff1a\u4ece\u6839\u5bf9\u8c61\uff08\u5982\u6d3b\u52a8\u7ebf\u7a0b\u7684\u5806\u6808\u6307\u9488\u3001\u9759\u6001\u5bf9\u8c61\u7b49\uff09\u5f00\u59cb\uff0c\u9012\u5f52\u904d\u5386\u6240\u6709\u53ef\u8fbe\u7684\u5bf9\u8c61\uff0c\u5e76\u5c06\u5b83\u4eec\u6807\u8bb0\u4e3a\u6d3b\u52a8\u7684\u3002
\u6e05\u9664\u9636\u6bb5\uff1a\u904d\u5386\u5806\u5185\u5b58\u4e2d\u6240\u6709\u5bf9\u8c61\uff0c\u5bf9\u4e8e\u6ca1\u6709\u88ab\u6807\u8bb0\u4e3a\u6d3b\u52a8\u7684\u5bf9\u8c61\uff0c\u91ca\u653e\u5176\u5360\u7528\u7684\u5185\u5b58\u7a7a\u95f4\u3002
\u7f3a\u70b9\uff1a<\/p>\n
\u6574\u4e2a\u8fc7\u7a0b\u4e2d\u9700\u8981\u505c\u6b62\u5e94\u7528\u7a0b\u5e8f\uff0c\u5bfc\u81f4\u505c\u987f\u65f6\u95f4\uff08STW,Stop-The-World\uff09\u3002
\u4f1a\u4ea7\u751f\u5185\u5b58\u788e\u7247\u3002<\/p>\n
<\/p>\n<\/li>\n
- \u6807\u8bb0-\u6574\u7406\n
\u6807\u8bb0-\u6574\u7406\u7b97\u6cd5\u662f\u6807\u8bb0-\u6e05\u9664\u7684\u6539\u8fdb\u7248\u3002\u5728\u6807\u8bb0\u6d3b\u52a8\u5bf9\u8c61\u4e4b\u540e\uff0c\u5b83\u4f1a\u5c06\u6240\u6709\u5b58\u6d3b\u7684\u5bf9\u8c61\u79fb\u5230\u5185\u5b58\u7684\u4e00\u7aef\uff0c\u7136\u540e\u6e05\u7406\u6389\u7aef\u8fb9\u754c\u5916\u7684\u5185\u5b58\u7a7a\u95f4\u3002<\/p>\n
\u4f18\u70b9\uff1a<\/p>\n
\u89e3\u51b3\u4e86\u5185\u5b58\u788e\u7247\u95ee\u9898\uff0c\u4e0d\u9700\u8981\u590d\u5236\u6d3b\u52a8\u5bf9\u8c61\u3002
\u7f3a\u70b9\uff1a<\/p>\n
\u9700\u8981\u79fb\u52a8\u5b58\u6d3b\u5bf9\u8c61\uff0c\u53ef\u80fd\u4f1a\u9020\u6210\u8f83\u5927\u7684\u5185\u5b58\u8fc1\u79fb\u5f00\u9500\u3002
\u9700\u8981\u8f83\u591a\u7684\u505c\u987f\u65f6\u95f4\uff0c\u4e0d\u9002\u5408\u5bf9\u54cd\u5e94\u65f6\u95f4\u8981\u6c42\u8f83\u9ad8\u7684\u5e94\u7528<\/p>\n<\/li>\n
- \u590d\u5236\n
\u590d\u5236\u7b97\u6cd5\u5c06\u5806\u5185\u5b58\u5206\u4e3a\u4e24\u534a\uff1a\u4e00\u534a\u7528\u4e8e\u5206\u914d\u5185\u5b58\uff0c\u53e6\u4e00\u534a\u5904\u4e8e\u7a7a\u95f2\u72b6\u6001\u3002\u5728\u5783\u573e\u6536\u96c6\u671f\u95f4\uff0c\u5b83\u5c06\u6240\u6709\u6d3b\u52a8\u5bf9\u8c61\u4ece\u5f53\u524d\u7684\u5185\u5b58\u533a\u57df\u590d\u5236\u5230\u53e6\u4e00\u534a\uff0c\u63a5\u7740\u6e05\u9664\u539f\u6709\u7684\u5185\u5b58\u533a\u57df\u4e2d\u7684\u6240\u6709\u5bf9\u8c61\u3002<\/p>\n
\u4f18\u70b9\uff1a<\/p>\n
\u89e3\u51b3\u4e86\u5185\u5b58\u788e\u7247\u95ee\u9898\uff0c\u9002\u5408\u5b58\u6d3b\u5bf9\u8c61\u8f83\u5c11\u573a\u666f\u3002
\u7f3a\u70b9\uff1a<\/p>\n
\u4e0d\u9002\u7528\u4e8e\u5904\u7406\u5b58\u6d3b\u8f83\u591a\u5bf9\u8c61\u7684\u573a\u666f
\u4f1a\u5360\u7528\u53cc\u500d\u5185\u5b58\u7a7a\u95f4<\/p>\n<\/li>\n<\/ol>\n\n\n
\n\n\nMinor GC\u548cFULL GC\u7684\u533a\u522b<\/h2>\nMinor GC<\/h3>\n
Minor GC\u53c8\u79f0\u4e3aYoung Generation GC\uff0c\u662f\u5728\u5e74\u8f7b\u4ee3\uff08Young Generation\uff09<\/strong>\u4e2d\u53d1\u751f\u7684\u5783\u573e\u56de\u6536\u3002<\/p>\n\u5e74\u8f7b\u4ee3\u901a\u5e38\u5305\u542b\u4e09\u4e2a\u90e8\u5206\uff1a<\/p>\n
Eden\u7a7a\u95f4\uff1a\u51e0\u4e4e\u6240\u6709\u65b0\u751f\u6210\u7684\u5bf9\u8c61\u9996\u5148\u90fd\u662f\u5728\u8fd9\u91cc\u5206\u914d\u7684\u3002
\u4e24\u4e2aSurvivor\u7a7a\u95f4\uff08\u901a\u5e38\u79f0\u4e3aFrom\u548cTo\u6216\u8005S0\u548cS1\uff09\uff1a\u7528\u6765\u5b58\u653e\u4eceEden\u548c\u81ea\u5df1\u533a\u57df\u4e2d\u7ecf\u8fc7\u7b2c\u4e00\u6b21Minor
GC\u540e\u4ecd\u7136\u5b58\u6d3b\u7684\u5bf9\u8c61\u3002
Minor GC\u7684\u8fc7\u7a0b\u901a\u5e38\u662f\u8fd9\u6837\u7684\uff1a<\/p>\n
\u65b0\u5bf9\u8c61\u88ab\u5206\u914d\u5230Eden\u533a\uff0c\u5f53Eden\u533a\u6ee1\u4e86\u4e4b\u540e\uff0c\u89e6\u53d1Minor GC\u3002
\u5b58\u6d3b\u7684\u5bf9\u8c61\u4eceEden\u533a\u590d\u5236\u5230\u4e00\u4e2aSurvivor\u533a\uff08From\uff09\u3002
\u5982\u679c\u5b58\u5728\u4e4b\u524d\u5df2\u7ecf\u7ecf\u8fc7\u4e00\u6b21Minor GC\u7684\u5bf9\u8c61\uff0c\u5b83\u4eec\u4f1a\u88ab\u4ece\u4e00\u4e2aSurvivor\u533a\u590d\u5236\u5230\u53e6\u4e00\u4e2a\uff08\u4eceFrom\u5230To\uff09\uff0c\u540c\u65f6\u5bf9\u8c61\u7684\u5e74\u9f84\u4f1a\u589e\u52a0\u3002\u5f53\u5bf9\u8c61\u5e74\u9f84\u8fbe\u5230\u4e00\u5b9a\u9608\u503c\u4e4b\u540e\uff0c\u5b83\u4eec\u4f1a\u88ab\u664b\u5347\u5230\u8001\u5e74\u4ee3\uff08Old Generation\uff09\u3002
\u7ecf\u8fc7\u5783\u573e\u56de\u6536\u540e\uff0cEden\u533a\u548c\u4e00\u4e2aSurvivor\u533a\uff08\u4ece\u54ea\u91cc\u590d\u5236\u7684\uff09\u4f1a\u88ab\u6e05\u7a7a\u3002
Minor GC\u7684\u7279\u70b9\u662f\u9891\u7e41\u4e14\u901f\u5ea6\u5feb\u3002\u5b83\u53ea\u662f\u9488\u5bf9\u5e74\u8f7b\u4ee3\u7684\u5783\u573e\u56de\u6536\uff0c\u800c\u4e14\u901a\u5e38\u60c5\u51b5\u4e0b\u53ea\u4f1a\u56de\u6536\u4e00\u5c0f\u90e8\u5206\u5185\u5b58\u7a7a\u95f4\u3002<\/p>\n<\/p>\n
FULL\u00a0 GC<\/h3>\n
Full GC\uff0c\u53c8\u79f0\u4e3aMajor GC\u6216Old Generation GC\uff0c\u6d89\u53ca\u6574\u4e2aJava\u5806\uff08Heap\uff09\u7684\u56de\u6536\uff0c\u5373\u5305\u62ec\u5e74\u8f7b\u4ee3\u3001\u8001\u5e74\u4ee3\uff08Old Generation\uff09\uff0c\u4ee5\u53ca\u65b9\u6cd5\u533a\uff08\u4e5f\u79f0\u4e3a\u6c38\u4e45\u4ee3\u5728JDK 7\u6216\u4e4b\u524d\u7684\u7248\u672c\uff0c\u6216\u8005\u5143\u7a7a\u95f4\u5728JDK 8\u4ee5\u540e\u7684\u7248\u672c\uff09\u3002<\/strong><\/p>\nFull GC\u7684\u8fc7\u7a0b\u76f8\u5bf9\u6765\u8bf4\u6bd4Minor GC\u8981\u590d\u6742\u4e14\u8017\u65f6\uff1a<\/p>\n
\u5bf9\u5e74\u8f7b\u4ee3\u6267\u884cMinor GC\u3002
\u7136\u540e\u8001\u5e74\u4ee3\u7684\u5bf9\u8c61\u4e5f\u4f1a\u88ab\u68c0\u67e5\uff0c\u4e0d\u518d\u5b58\u6d3b\u7684\u5bf9\u8c61\u4f1a\u88ab\u6e05\u9664\u3002
\u65b9\u6cd5\u533a\/\u5143\u7a7a\u95f4\u4e2d\u4e0d\u518d\u4f7f\u7528\u7684\u7c7b\u548c\u9759\u6001\u5185\u5bb9\u5c06\u88ab\u56de\u6536\u3002
\u8bc6\u522b\u8001\u5e74\u4ee3\u4e2d\u53ef\u4ee5\u79fb\u52a8\u7684\u5bf9\u8c61\uff0c\u5e76\u6574\u7406\u5185\u5b58\u7a7a\u95f4\uff0c\u4ece\u800c\u5728\u8001\u5e74\u4ee3\u4e2d\u4e5f\u80fd\u9ad8\u6548\u5730\u5206\u914d\u5185\u5b58\u3002
Full GC\u53d1\u751f\u7684\u65f6\u5019\uff0c\u901a\u5e38\u4f1a\u89e6\u53d1STW\uff08Stop-The-World\uff09\uff0c\u5373\u6240\u6709\u7684\u5e94\u7528\u7ebf\u7a0b\u90fd\u4f1a\u88ab\u6682\u505c\uff0c\u76f4\u5230GC\u5b8c\u6210\u3002<\/p>\n<\/p>\n
\u89e6\u53d1\u6761\u4ef6<\/h3>\n
Minor GC\u548cFull GC\u7684\u89e6\u53d1\u6761\u4ef6\u5404\u4e0d\u76f8\u540c\uff1a<\/p>\n
Minor GC\u901a\u5e38\u662f\u5f53\u5e74\u8f7b\u4ee3\u7684Eden\u533a\u6ee1\u4e86\u65f6\u89e6\u53d1\u3002<\/p>\n
Full GC\u53ef\u80fd\u7531\u4ee5\u4e0b\u51e0\u4e2a\u6761\u4ef6\u89e6\u53d1\uff1a<\/p>\n
\u8001\u5e74\u4ee3\u7a7a\u95f4\u4e0d\u8db3\u3002
\u65b9\u6cd5\u533a\/\u5143\u7a7a\u95f4\u5185\u5b58\u4e0d\u8db3\u3002
System.gc()\u65b9\u6cd5\u7684\u8c03\u7528\u3002
JVM\u7684\u5185\u5b58\u56de\u6536\u7b56\u7565\u3002<\/p>\n\n\n
\n\n\n\u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565<\/h2>\n\u5b9a\u4e49<\/h3>\n
\u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565\uff08Promotion Guarantee\uff09\u662fJVM\u4e2d\u7684\u4e00\u79cd\u673a\u5236\uff0c\u786e\u4fdd\u5728Minor GC\u65f6\uff0c\u5b58\u6d3b\u7684\u5bf9\u8c61\u80fd\u591f\u6210\u529f\u664b\u5347\u5230\u8001\u5e74\u4ee3\u3002\u5982\u679c\u8001\u5e74\u4ee3\u6ca1\u6709\u8db3\u591f\u7684\u7a7a\u95f4\u6765\u63a5\u6536\u65b0\u664b\u5347\u7684\u5bf9\u8c61\uff0cJVM\u53ef\u80fd\u4f1a\u63d0\u524d\u89e6\u53d1\u4e00\u6b21Full GC\u6765\u91ca\u653e\u7a7a\u95f4\uff0c\u6216\u8005\u8c03\u6574\u81ea\u5df1\u7684\u5185\u5b58\u5206\u914d\u7b56\u7565\u4ee5\u907f\u514d\u6b64\u7c7b\u60c5\u51b5\u7684\u53d1\u751f\u3002<\/p>\n
\u5de5\u4f5c\u539f\u7406<\/h3>\n\n- jdk6 \u4ee5\u524d \u8981\u6839\u636e\u662f\u5426\u5141\u8bb8\u62c5\u4fdd\u5931\u8d25\u6765\u91c7\u53d6\u4e0d\u540c\u7684\u51fa\u53d1FULL GC\u7684\u6761\u4ef6\uff0c\u5982\u679c\u4e0d\u5141\u8bb8\uff0c\u6211\u4eec\u5c31\u8981\u5224\u65ad\u65b0\u751f\u4ee3\u7684\u5168\u90e8\u5bf9\u8c61\u7a7a\u95f4\u662f\u5426\u5c0f\u4e8e\u8001\u5e74\u4ee3\u5269\u4f59\u8fde\u7eed\u5185\u5b58\u7a7a\u95f4\n
\u5728\u8fdb\u884cMinor GC\u524d\uff0c\u865a\u62df\u673a\u4f1a\u68c0\u67e5\u8001\u5e74\u4ee3\u6700\u5927\u53ef\u7528\u7684\u8fde\u7eed\u7a7a\u95f4\u662f\u5426\u5927\u4e8e\u65b0\u751f\u4ee3\u6240\u6709\u5bf9\u8c61\u603b\u7a7a\u95f4\u3002\u5982\u679c\u8fd9\u4e2a\u6761\u4ef6\u4e0d\u80fd\u6ee1\u8db3\uff0c\u865a\u62df\u673a\u4f1a\u67e5\u770b -XX:HandlePromotionFailure \u8bbe\u7f6e\u662f\u5426\u5141\u8bb8\u62c5\u4fdd\u5931\u8d25\u3002\u5982\u679c\u4e0d\u5141\u8bb8\uff08false\uff09\uff0c\u90a3\u4e48\u4f1a\u63d0\u524d\u8fdb\u884c\u4e00\u6b21Full GC\u6765\u6e05\u7406\u8001\u5e74\u4ee3\u5e76\u4e3a\u65b0\u751f\u4ee3\u664b\u5347\u7684\u5bf9\u8c61\u817e\u51fa\u7a7a\u95f4\u3002\u5982\u679c\u5141\u8bb8\u62c5\u4fdd\u5931\u8d25\uff08true\uff09\uff0c\u90a3\u4e48\u53ea\u8981\u8001\u5e74\u4ee3\u5269\u4f59\u7a7a\u95f4\u5927\u4e8e\u5386\u6b21\u664b\u5347\u5230\u8001\u5e74\u4ee3\u5bf9\u8c61\u7684\u5e73\u5747\u5927\u5c0f\u5373\u53ef\u8fdb\u884cMinor GC\uff0c\u5426\u5219\u4e5f\u8981\u63d0\u524d\u8fdb\u884cFull GC\u3002<\/p>\n<\/li>\n
- \n
\u4eceJDK 7\u5f00\u59cb\uff0cHotSpot\u865a\u62df\u673a\u7684\u5783\u573e\u6536\u96c6\u5668\u5728\u505aMinor GC\u4e4b\u524d\u7684\u7a7a\u95f4\u5206\u914d\u62c5\u4fdd\u7b56\u7565\u4e0a\u8fdb\u884c\u4e86\u8c03\u6574\uff0c\u53d6\u6d88\u4e86\u4e4b\u524d\u7248\u672c\u4e2d\u7684 -XX:HandlePromotionFailure \u9009\u9879\u3002\u6bcf\u6b21\u90fd\u4f1a\u5224\u65ad\u8001\u5e74\u4ee3\u5269\u4f59\u6700\u5927\u8fde\u7eed\u7a7a\u95f4\u5927\u4e8e\u5386\u6b21Minor GC\u664b\u5347\u7684\u5e73\u5747\u5927\u5c0f \u6216\u8005 \u5927\u4e8e\u65b0\u751f\u4ee3\u6240\u6709\u5bf9\u8c61\u7684\u5927\u5c0f\u603b\u548c \uff0c \u5927\u4e8e\u4efb\u610f\u4e00\u4e2a\uff0c\u5c31\u5141\u8bb8\u89e6\u53d1MinorGC\uff0c\u53cd\u4e4b\u89e6\u53d1 Full GC
jdk6\u4e4b\u540e \u5c31\u6ca1\u6709\u662f\u5426\u5141\u8bb8\u62c5\u4fdd\u5931\u8d25\u7684\u9009\u9879\u4e86<\/p>\n
\u00a0<\/p>\n<\/li>\n<\/ul>\n
\u5982\u4f55\u8c03\u4f18\u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565<\/h3>\n
\u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565\u7684\u8c03\u4f18\u901a\u5e38\u6d89\u53ca\u51e0\u4e2a\u5173\u952e\u7684JVM\u53c2\u6570\uff1a<\/p>\n
-XX:SurvivorRatio: \u8bbe\u7f6e\u65b0\u751f\u4ee3\u4e2dEden\u533a\u4e0eSurvivor\u533a\u7684\u6bd4\u4f8b\u3002
-XX:NewRatio: \u8bbe\u7f6e\u65b0\u751f\u4ee3\u4e0e\u8001\u5e74\u4ee3\u7684\u6bd4\u4f8b\u3002
-XX:MaxTenuringThreshold: \u8bbe\u7f6e\u5bf9\u8c61\u5728\u65b0\u751f\u4ee3\u7684\u5b58\u6d3b\u6b21\u6570\uff0c\u8d85\u8fc7\u8fd9\u4e2a\u6b21\u6570\u7684\u5bf9\u8c61\u4f1a\u88ab\u664b\u5347\u5230\u8001\u5e74\u4ee3\u3002
-XX:PretenureSizeThreshold: \u8bbe\u7f6e\u5927\u5c0f\u9608\u503c\uff0c\u8d85\u8fc7\u8fd9\u4e2a\u5927\u5c0f\u7684\u5bf9\u8c61\u4e0d\u4f1a\u5728\u65b0\u751f\u4ee3\u5206\u914d\uff0c\u800c\u76f4\u63a5\u5728\u8001\u5e74\u4ee3\u5206\u914d\u3002
\u8c03\u4f18\u901a\u5e38\u9700\u8981\u6839\u636e\u5e94\u7528\u7a0b\u5e8f\u7684\u5177\u4f53\u60c5\u51b5\u6765\u8fdb\u884c\u3002\u76d1\u63a7\u5de5\u5177\uff08\u5982jstat, VisualVM\u6216\u5176\u4ed6\u5546\u4e1a\u76d1\u63a7\u5de5\u5177\uff09\u53ef\u4ee5\u5e2e\u52a9\u4f60\u7406\u89e3\u5185\u5b58\u4f7f\u7528\u60c5\u51b5\uff0c\u5e76\u636e\u6b64\u505a\u51fa\u8c03\u6574\u3002<\/p>\n
\u603b\u7ed3<\/h3>\n
\u5982\u679c\u6ca1\u6709\u7a7a\u95f4\u62c5\u4fdd\uff0cMinor GC\u4f1a\u8fdb\u884c\u5c1d\u8bd5\uff0c\u5f88\u53ef\u80fd\u5728\u664b\u5347\u8fc7\u7a0b\u4e2d\u5931\u8d25\uff0c\u56e0\u4e3a\u8001\u5e74\u4ee3\u6ca1\u6709\u8db3\u591f\u7684\u7a7a\u95f4\u3002\u8fd9\u65f6JVM\u53ef\u80fd\u4f1a\u629b\u51fa OutOfMemoryError\uff0c\u6216\u8005\u5c1d\u8bd5\u4e00\u6b21\u6602\u8d35\u7684Full GC\u6765\u5f3a\u5236\u56de\u6536\u7a7a\u95f4\u3002<\/p>\n
\u800c\u5f00\u542f\u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565\uff0cJVM\u5728\u5f00\u59cbMinor GC\u4e4b\u524d\u4f1a\u68c0\u67e5\u8001\u5e74\u4ee3\u662f\u5426\u6709\u8db3\u591f\u7684\u7a7a\u95f4\u3002\u5728\u8fd9\u4e2a\u60c5\u51b5\u4e0b\uff0cJVM\u4f1a\u8ba4\u8bc6\u5230\u8001\u5e74\u4ee3\u7a7a\u95f4\u4e0d\u8db3\uff0c\u56e0\u6b64\u53ef\u80fd\u76f4\u63a5\u89e6\u53d1Full GC\uff0c\u6765\u786e\u4fdd\u4e0d\u4f1a\u5728Minor GC\u8fc7\u7a0b\u4e2d\u51fa\u73b0\u5185\u5b58\u5206\u914d\u5931\u8d25\u3002<\/p>\n
\u603b\u4e4b\uff0c\u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565\u662f\u4e00\u79cd\u9884\u9632\u63aa\u65bd\uff0c\u4fdd\u969cJVM\u5728\u8fdb\u884cMinor GC\u65f6\u7684\u5185\u5b58\u5206\u914d\u5b89\u5168\u6027\uff0c\u5c3d\u91cf\u51cf\u5c11Full GC\u7684\u53d1\u751f\uff0c\u4ee5\u63d0\u9ad8\u7cfb\u7edf\u7684\u6027\u80fd\u548c\u7a33\u5b9a\u6027\u3002<\/p>\n
\u6ce8\uff1a\u6bcf\u6b21\u7684\u5783\u573e\u56de\u6536\u90fd\u662f\u5bf9\u7cfb\u7edf\u8d44\u6e90\u7684\u4e00\u6b21\u6d88\u8017\uff0c\u56e0\u6b64\u9002\u5f53\u7684\u8c03\u4f18\u53ef\u4ee5\u51cf\u5c11GC\u7684\u6b21\u6570\u548c\u5f71\u54cd\uff0c\u4ece\u800c\u4e3a\u5e94\u7528\u7a0b\u5e8f\u63d0\u4f9b\u66f4\u5e73\u6ed1\u7684\u6027\u80fd\u4f53\u9a8c\u3002<\/p>\n\n\n
\n\n\n\n\u5783\u573e\u56de\u6536\u5668<\/h2>\nSerial GC<\/h3>\n
![\"image\"](\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\")
<\/div><\/p>\nParallel GC<\/h3>\n
<\/div><\/p>\n\u00a0<\/p>\n
CMS GC<\/h3>\n
<\/div><\/p>\nG1 GC<\/h3>\n
<\/div><\/p>\nZ GC<\/h3>\n
ZGC\u662f\u4e00\u79cd\u4f4e\u5ef6\u8fdf\u7684\u5783\u573e\u56de\u6536\u5668\uff0c\u76ee\u524d\u4ecd\u5728\u79ef\u6781\u5f00\u53d1\u4e2d\u3002ZGC\u7684\u8bbe\u8ba1\u521d\u8877\u662f\u4e3a\u4e86\u5728\u5927\u5806\u5185\u5b58\u4e0a\u5de5\u4f5c\uff0c\u5e76\u4e14\u51e0\u4e4e\u4e0d\u4ea7\u751f\u5ef6\u8fdf\u3002\u8fd9\u4f7f\u5f97\u5b83\u975e\u5e38\u9002\u5408\u9700\u8981\u5feb\u901f\u54cd\u5e94\u4f46\u662f\u5185\u5b58\u5360\u7528\u5927\u7684\u5e94\u7528\u7a0b\u5e8f\u3002<\/p>\n
\u4f7f\u7528\u53c2\u6570\uff1a<\/p>\n
-XX:+UseZGC<\/p>\n
Shenandoah GC<\/h3>\n
Shenandoah GC\u4e0eZGC\u6709\u7c7b\u4f3c\u7684\u76ee\u6807\uff1a\u51cf\u5c11\u505c\u987f\u65f6\u95f4\uff0c\u5373\u4fbf\u662f\u5728\u5927\u5806\u6216\u8005\u591a\u6838\u5fc3\u5904\u7406\u5668\u7684\u60c5\u51b5\u4e0b\u3002Shenandoah\u901a\u8fc7\u5728GC\u7684\u8bb8\u591a\u9636\u6bb5\u4e0e\u5e94\u7528\u7ebf\u7a0b\u5e76\u53d1\u6267\u884c\u6765\u5b9e\u73b0\u8fd9\u4e00\u76ee\u6807\u3002<\/p>\n
\u4f7f\u7528\u53c2\u6570\uff1a<\/p>\n
-XX:+UseShenandoahGC<\/p>\n
\u5982\u4f55\u9009\u62e9\u5408\u9002\u7684\u5783\u573e\u5904\u7406\u5668<\/h3>\n
\u5728\u9009\u62e9\u5783\u573e\u56de\u6536\u5668\u65f6\uff0c\u9700\u8981\u8003\u8651\u5e94\u7528\u7a0b\u5e8f\u7684\u9700\u6c42\uff1a<\/p>\n
\u5bf9\u4e8e\u9700\u8981\u6700\u5927\u541e\u5410\u91cf\u7684\u5e94\u7528\u7a0b\u5e8f\uff0cParallel GC\u53ef\u80fd\u662f\u6700\u597d\u7684\u9009\u62e9\u3002
\u5982\u679c\u5e94\u7528\u9700\u8981\u8f83\u77ed\u7684\u54cd\u5e94\u65f6\u95f4\u6216\u8005\u8f83\u5c11\u7684\u505c\u987f\u65f6\u95f4\uff0c\u53ef\u4ee5\u8003\u8651CMS\u6216G1\u3002
\u5bf9\u4e8e\u9700\u8981\u6781\u4f4e\u505c\u987f\u65f6\u95f4\u5e76\u4e14\u5177\u6709\u5927\u5185\u5b58\u5bb9\u91cf\u7684\u5e94\u7528\uff0cZGC\u6216\u8005Shenandoah\u53ef\u80fd\u662f\u5408\u9002\u7684\u9009\u62e9\u3002
\u5728\u5b9e\u9645\u4e2d\uff0c\u6700\u597d\u7684\u65b9\u6cd5\u662f\u901a\u8fc7\u5b9e\u9645\u7684\u6027\u80fd\u6d4b\u8bd5\u6765\u786e\u5b9a\u6700\u9002\u5408\u4f60\u7684\u5e94\u7528\u7684\u5783\u573e\u56de\u6536\u5668\u3002<\/p>\n
JDK8\u9ed8\u8ba4\u56de\u6536\u5904\u7406\u5668<\/h3>\n
JDK 8\uff08Java Development Kit 8\uff09\u4e2d\u9ed8\u8ba4\u7684\u5783\u573e\u56de\u6536\u5668\u7ec4\u5408\u4e3aParallel Scavenge\uff08\u7528\u4e8eYoung Generation\uff09\u52a0\u4e0aParallel Old\uff08\u7528\u4e8eOld Generation\uff09\u3002Parallel GC \u5728 JDK 5 \u4e2d\u5f00\u59cb\u6210\u4e3a\u9ed8\u8ba4\u7684\u5783\u573e\u56de\u6536\u5668\uff0c\u7279\u70b9\uff1a\u5e76\u884c+STW\u3002<\/p>\n
Parallel Scavenge\u6536\u96c6\u5668\u662f\u4e00\u4e2a\u65b0\u751f\u4ee3\u5783\u573e\u6536\u96c6\u5668\uff0c\u5b83\u4f7f\u7528\u590d\u5236\u7b97\u6cd5\uff0c\u800c\u4e14\u662f\u5e76\u884c\u7684\u591a\u7ebf\u7a0b\u6536\u96c6\u5668\u3002\u5b83\u4e3b\u8981\u5173\u6ce8\u4e8e\u8fbe\u5230\u4e00\u4e2a\u53ef\u63a7\u5236\u7684\u541e\u5410\u91cf\uff08Throughput\uff09\u3002\u6240\u8c13\u541e\u5410\u91cf\uff0c\u5c31\u662fCPU\u7528\u4e8e\u8fd0\u884c\u7528\u6237\u4ee3\u7801\u7684\u65f6\u95f4\u4e0eCPU\u603b\u6d88\u8017\u65f6\u95f4\u7684\u6bd4\u503c\uff0c\u5373\uff1a\u541e\u5410\u91cf = \u7528\u6237\u4ee3\u7801\u65f6\u95f4 \/\uff08\u7528\u6237\u4ee3\u7801\u65f6\u95f4 + \u5783\u573e\u6536\u96c6\u65f6\u95f4\uff09\u3002\u670d\u52a1\u5668\u73af\u5883\u4e2d\uff0c\u8fd9\u79cd\u6536\u96c6\u5668\u80fd\u591f\u6700\u5927\u5316\u7684\u5229\u7528CPU\u65f6\u95f4\uff0c\u5c3d\u5feb\u5730\u5b8c\u6210\u7a0b\u5e8f\u7684\u8fd0\u7b97\u4efb\u52a1\uff0c\u7279\u522b\u9002\u7528\u4e8e\u591a\u6838\u670d\u52a1\u5668\u3002<\/p>\n
Parallel Old\u6536\u96c6\u5668\u662fParallel Scavenge\u6536\u96c6\u5668\u7684\u8001\u5e74\u4ee3\u7248\u672c\uff0c\u4f7f\u7528\u591a\u7ebf\u7a0b\u548c”\u6807\u8bb0-\u6574\u7406”\u7b97\u6cd5\u3002\u8fd9\u4e2a\u6536\u96c6\u5668\u662f\u5728JDK 6u14\u7248\u4e4b\u540e\u5f15\u5165\u7684\u3002\u4eceJDK 9 \u5f00\u59cb\u9ed8\u8ba4\u5783\u573e\u56de\u6536\u5668\u662f G1 (Garbage-First)<\/p>\n
CMS\u4e0d\u4f5c\u4e3a\u9ed8\u8ba4\u5904\u7406\u5668\u7684\u539f\u56e0<\/h3>\n
CMS\uff08Concurrent Mark-Sweep\uff09\u6536\u96c6\u5668\u662f\u4e00\u4e2a\u4ee5\u83b7\u53d6\u6700\u77ed\u56de\u6536\u505c\u987f\u65f6\u95f4\u4e3a\u76ee\u6807\u7684\u6536\u96c6\u5668\uff0c\u4f7f\u7528”\u6807\u8bb0-\u6e05\u9664”\u7b97\u6cd5\uff0c\u5e76\u4e14\u662f\u5e76\u53d1\u7684\u3002\u4f46\u662f\u5728JDK\u7248\u672c\u7684\u8fed\u4ee3\u4e2d\u6ca1\u6709\u4efb\u4f55\u4e00\u4e2a\u7248\u672c\u4f7f\u7528CMS\u4e3a\u4e00\u4e2a\u9ed8\u8ba4\u7684\u5783\u573e\u56de\u6536\u5668\u3002<\/p>\n
\u9009\u62e9Parallel Scavenge\u548cParallel Old\u7684\u539f\u56e0\u800c\u4e0d\u7528CMS\uff0c\u901a\u5e38\u57fa\u4e8e\u4ee5\u4e0b\u8003\u8651\uff1a<\/p>\n
\u541e\u5410\u91cf\u4f18\u5148\uff1a \u5982\u679c\u5e94\u7528\u4e0d\u662f\u975e\u5e38\u6ce8\u91cd\u670d\u52a1\u54cd\u5e94\u65f6\u95f4\uff0c\u800c\u662f\u66f4\u5e0c\u671b\u5728\u5355\u4f4d\u65f6\u95f4\u5185\u5b8c\u6210\u66f4\u591a\u7684\u5de5\u4f5c\uff0c\u5373\u8ffd\u6c42\u8f83\u9ad8\u7684\u541e\u5410\u91cf\uff0c\u90a3\u4e48Parallel Scavenge\u52a0\u4e0aParallel Old\u5783\u573e\u6536\u96c6\u5668\u4f1a\u662f\u4e00\u4e2a\u66f4\u5408\u9002\u7684\u9009\u62e9\u3002<\/p>\n
\u788e\u7247\u5316\u95ee\u9898\uff1aCMS\u4f7f\u7528\u7684”\u6807\u8bb0-\u6e05\u9664”\u7b97\u6cd5\u5bb9\u6613\u5bfc\u81f4\u5185\u5b58\u788e\u7247\u5316\uff0c\u5f53\u788e\u7247\u5316\u4e25\u91cd\u5230\u4e00\u5b9a\u7a0b\u5ea6\uff0cCMS\u9700\u8981\u8fdb\u884c\u4e00\u6b21\u5b8c\u5168\u505c\u987f\u7684\u5783\u573e\u6536\u96c6\u4ee5\u6574\u7406\u5185\u5b58\u788e\u7247\uff08Full GC\uff09\uff0c\u8fd9\u53ef\u80fd\u5bfc\u81f4\u8f83\u957f\u65f6\u95f4\u7684\u505c\u987f\u3002\u800cParallel Old\u4f7f\u7528\u7684”\u6807\u8bb0-\u6574\u7406”\u7b97\u6cd5\u53ef\u4ee5\u6709\u6548\u907f\u514d\u5185\u5b58\u788e\u7247\u5316\u95ee\u9898\u3002<\/p>\n
\u66f4\u7b80\u5355\u7a33\u5b9a\uff1a \u76f8\u8f83\u4e8eCMS\uff0cParallel Scavenge\u548cParallel Old\u901a\u5e38\u6765\u8bf4\u7ef4\u62a4\u8d77\u6765\u6bd4\u8f83\u7b80\u5355\uff0c\u53c2\u6570\u914d\u7f6e\u4e5f\u66f4\u5bb9\u6613\u3002\u800cCMS\u6709\u51e0\u767e\u4e2a\u53c2\u6570\u9700\u8981\u914d\u7f6e\u8c03\u6574\uff0c\u5bf9\u4e8e\u7ef4\u62a4\u7684\u6210\u672c\u662f\u975e\u5e38\u9ad8\u7684\u3002<\/p>\n
\u968f\u7740Java 9\u7684\u53d1\u5e03\uff0cG1\uff08Garbage-First\uff09\u5783\u573e\u6536\u96c6\u5668\u6210\u4e3a\u4e86\u9ed8\u8ba4\u7684\u5783\u573e\u6536\u96c6\u5668\uff0c\u5b83\u65e8\u5728\u66ff\u4ee3CMS\uff0c\u63d0\u4f9b\u66f4\u597d\u7684\u6027\u80fd\u8868\u73b0\u548c\u66f4\u7b80\u5355\u7684\u8c03\u4f18\u9009\u9879\u3002\u800c\u5728Java 11\u4e4b\u540e\uff0c\u8fd8\u5f15\u5165\u4e86ZGC\u548cShenandoah\u7b49\u5b9e\u9a8c\u6027\u7684\u4f4e\u505c\u987f\u65f6\u95f4\u5783\u573e\u6536\u96c6\u5668\u3002<\/p>\n
CMS\u548cG1\u7684\u6bd4\u8f83<\/h3>\n
CMS\uff08Concurrent Mark Sweep\uff09\u548cG1\uff08Garbage-First\uff09\u662fJava\u865a\u62df\u673a\u4e2d\u7684\u4e24\u79cd\u4e0d\u540c\u7684\u5783\u573e\u56de\u6536\u5668\uff0c\u5b83\u4eec\u5404\u81ea\u6709\u4e0d\u540c\u7684\u7279\u70b9\u548c\u9002\u7528\u573a\u666f\u3002<\/p>\n
1.CMS\u5783\u573e\u56de\u6536\u6d41\u7a0b<\/strong>
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\u4f7f\u7528\u4e09\u8272\u6807\u8bb0\u6cd5\uff0c\u5bf9\u8c61\u88ab\u5206\u4e3a\u4e09\u79cd\u989c\u8272\uff1a\u767d\u8272\uff08\u672a\u88ab\u626b\u63cf\uff09\u3001\u7070\u8272\uff08\u5df2\u626b\u63cf\u4f46\u5176\u5f15\u7528\u5c1a\u672a\u5168\u90e8\u626b\u63cf\uff09\u3001\u9ed1\u8272\uff08\u5df2\u626b\u63cf\u4e14\u5176\u5f15\u7528\u4e5f\u5df2\u5168\u90e8\u626b\u63cf\uff09\u3002\u521d\u59cb\u65f6\uff0c\u6240\u6709\u5bf9\u8c61\u88ab\u89c6\u4e3a\u767d\u8272\u3002\u968f\u7740\u626b\u63cf\u7684\u8fdb\u884c\uff0c\u5bf9\u8c61\u4ece\u767d\u8272\u53d8\u4e3a\u7070\u8272\uff0c\u7136\u540e\u53d8\u4e3a\u9ed1\u8272\u3002\u6240\u6709\u53ef\u8fbe\u5bf9\u8c61\u6807\u8bb0\u4e3a\u9ed1\u8272\u3002
\u91cd\u65b0\u6807\u8bb0\uff1a\u7531\u4e8e\u5e76\u53d1\u6807\u8bb0\u9636\u6bb5\u7528\u6237\u7a0b\u5e8f\u4ecd\u5728\u8fd0\u884c\uff0c\u53ef\u80fd\u4f1a\u5bfc\u81f4\u90e8\u5206\u5bf9\u8c61\u7684\u6807\u8bb0\u72b6\u6001\u53d1\u751f\u6539\u53d8\uff0c\u91cd\u65b0\u6807\u8bb0\u9636\u6bb5\u5c31\u662f\u4e3a\u4e86\u4fee\u6b63\u8fd9\u4e9b\u53d8\u52a8\u3002
\u591a\u4e2aGC\u7ebf\u7a0bSTW\u8fdb\u884c\u3002
\u5e76\u53d1\u6e05\u7406\uff1a\u591a\u4e2aGC\u7ebf\u7a0b\u5e76\u53d1\u6e05\u7406\u90a3\u4e9b\u5728\u6807\u8bb0\u9636\u6bb5\u88ab\u6807\u8bb0\u4e3a\u5783\u573e\uff08\u5373\u672a\u88ab\u6807\u8bb0\u4e3a\u9ed1\u8272\u7684\u5bf9\u8c61\uff09\u7684\u5bf9\u8c61\uff0c\u91ca\u653e\u5185\u5b58\u7a7a\u95f4\u3002
\u5e76\u53d1\u91cd\u7f6e\uff1a\u591a\u4e2aGC\u7ebf\u7a0b\u5e76\u53d1\u5c06\u5b58\u6d3b\u5bf9\u8c61\u4e0a\u7684\u6807\u8bb0\u7ed9\u79fb\u9664\u6389\uff0c\u907f\u514d\u5f71\u7b49\u4e0b\u6b21gc
2. G1\u5783\u573e\u56de\u6536\u6d41\u7a0b<\/strong>
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\u5e76\u53d1\u6807\u8bb0:\u591a\u4e2aGC\u7ebf\u7a0b\u548c\u7528\u6237\u7ebf\u7a0b\u540c\u65f6\u5de5\u4f5c\uff0c\u4eceGC Roots\u5f00\u59cb\u904d\u5386\u6574\u4e2a\u5bf9\u8c61\u56fe\uff0c\u627e\u51fa\u6240\u6709\u53ef\u8fbe\u5bf9\u8c61\u3002
\u4f7f\u7528\u4e09\u8272\u6807\u8bb0\u6cd5\uff0c\u5bf9\u8c61\u88ab\u5206\u4e3a\u4e09\u79cd\u989c\u8272\uff1a\u767d\u8272\uff08\u672a\u88ab\u626b\u63cf\uff09\u3001\u7070\u8272\uff08\u5df2\u626b\u63cf\u4f46\u5176\u5f15\u7528\u5c1a\u672a\u5168\u90e8\u626b\u63cf\uff09\u3001\u9ed1\u8272\uff08\u5df2\u626b\u63cf\u4e14\u5176\u5f15\u7528\u4e5f\u5df2\u5168\u90e8\u626b\u63cf\uff09\u3002\u521d\u59cb\u65f6\uff0c\u6240\u6709\u5bf9\u8c61\u88ab\u89c6\u4e3a\u767d\u8272\u3002\u968f\u7740\u626b\u63cf\u7684\u8fdb\u884c\uff0c\u5bf9\u8c61\u4ece\u767d\u8272\u53d8\u4e3a\u7070\u8272\uff0c\u7136\u540e\u53d8\u4e3a\u9ed1\u8272\u3002\u6240\u6709\u53ef\u8fbe\u5bf9\u8c61\u6807\u8bb0\u4e3a\u9ed1\u8272\u3002
\u6700\u7ec8\u6807\u8bb0:\u56e0\u4e3a\u4e0a\u4e2a\u8fc7\u7a0b\u662f\u5e76\u53d1\u8fdb\u884c\u7684,\u6240\u4ee5\u6709\u4e9b\u5bf9\u8c61\u662f\u5728\u6807\u8bb0\u8fc7\u7a0b\u4e2d\u65b0\u4ea7\u751f\u7684,\u5bfc\u81f4\u6ca1\u6709\u6807\u8bb0\u4e0a,\u6240\u4ee5\u8fd9\u4e2a\u8fc7\u7a0b\u8fdb\u884c\u4fee\u6b63\uff0c\u5c06\u8fd9\u4e9b\u6f0f\u7f51\u4e4b\u9c7c\u90fd\u6807\u4e0a\uff0c\u8fd9\u4e2a\u8fc7\u7a0b\u662f\u591a\u7ebf\u7a0b STW \u8fdb\u884c\u3002\u53ef\u4ee5\u901a\u8fc7\u589e\u91cf\u6807\u8bb0\u6216\u4f7f\u7528\u5199\u5c4f\u969c\u6280\u672f\u6765\u51cf\u5c11\u9700\u8981\u91cd\u65b0\u6807\u8bb0\u7684\u5bf9\u8c61\u6570\u91cf\u3002
\u7b5b\u9009\u56de\u6536:\u8ba1\u7b97\u6bcf\u4e2aregion\u7684\u56de\u6536\u6210\u672c\uff0c\u5e76\u6309\u7167\u56de\u6536\u6210\u672c\u8fdb\u884c\u6392\u5e8f\uff0c\u7136\u540e\u6309\u7167\u7528\u6237\u671f\u671b\u7684\u505c\u987f\u65f6\u95f4\u8fdb\u884c\u8ba1\u7b97\uff0c\u51b3\u5b9a\u5e94\u8be5\u56de\u6536\u54ea\u4e9bregion\u3002\u53ef\u4ee5\u901a\u8fc7\u66f4\u667a\u80fd\u7684region\u9009\u62e9\u7b97\u6cd5\u6765\u4f18\u5316\uff0c\u4f8b\u5982\u4f18\u5148\u56de\u6536\u5783\u573e\u5bf9\u8c61\u6700\u591a\u7684region\u6216\u56de\u6536\u6210\u672c\u6700\u4f4e\u7684region\u3002
G1\u6536\u96c6\u5668\u662f\u4e3a\u4e86\u66ff\u4ee3CMS\u6536\u96c6\u5668\u800c\u8bbe\u8ba1\u7684\uff0c\u63d0\u4f9b\u66f4\u53ef\u9884\u6d4b\u7684\u5783\u573e\u56de\u6536\u6682\u505c\u65f6\u95f4\uff0c\u7279\u522b\u662f\u5728\u5904\u7406\u5927\u5185\u5b58\u5bb9\u91cf\u7684\u591a\u5904\u7406\u5668\u673a\u5668\u65f6\u3002G1\u80fd\u591f\u66f4\u597d\u5730\u63a7\u5236\u505c\u987f\u65f6\u95f4\uff0c\u901a\u8fc7\u5c06\u5806\u5206\u5272\u6210\u591a\u4e2a\u533a\u57df\uff08Region\uff09\u6765\u907f\u514d\u6574\u4e2a\u5806\u7684\u5783\u573e\u56de\u6536\uff0c\u9010\u6b65\u5730\u6e05\u7406\u5185\u5b58\uff0c\u7279\u522b\u9002\u5408\u5927\u5806\u5185\u5b58\u7684\u5e94\u7528\u3002
3. \u4e24\u8005\u6bd4\u8f83<\/strong>
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\u5185\u5b58\u5360\u7528\uff1aG1\u901a\u5e38\u6bd4CMS\u9700\u8981\u66f4\u591a\u7684\u5185\u5b58\u7a7a\u95f4\uff0c\u56e0\u4e3a\u5b83\u9700\u8981\u7ef4\u62a4\u66f4\u591a\u7684\u5185\u5b58\u7ed3\u6784\u3002
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\u6e05\u9664\u9636\u6bb5\uff1a\u904d\u5386\u5806\u5185\u5b58\u4e2d\u6240\u6709\u5bf9\u8c61\uff0c\u5bf9\u4e8e\u6ca1\u6709\u88ab\u6807\u8bb0\u4e3a\u6d3b\u52a8\u7684\u5bf9\u8c61\uff0c\u91ca\u653e\u5176\u5360\u7528\u7684\u5185\u5b58\u7a7a\u95f4\u3002
\u7f3a\u70b9\uff1a<\/p>\n
\u6574\u4e2a\u8fc7\u7a0b\u4e2d\u9700\u8981\u505c\u6b62\u5e94\u7528\u7a0b\u5e8f\uff0c\u5bfc\u81f4\u505c\u987f\u65f6\u95f4\uff08STW,Stop-The-World\uff09\u3002
\u4f1a\u4ea7\u751f\u5185\u5b58\u788e\u7247\u3002<\/p>\n
<\/p>\n<\/li>\n
\u6807\u8bb0-\u6574\u7406\u7b97\u6cd5\u662f\u6807\u8bb0-\u6e05\u9664\u7684\u6539\u8fdb\u7248\u3002\u5728\u6807\u8bb0\u6d3b\u52a8\u5bf9\u8c61\u4e4b\u540e\uff0c\u5b83\u4f1a\u5c06\u6240\u6709\u5b58\u6d3b\u7684\u5bf9\u8c61\u79fb\u5230\u5185\u5b58\u7684\u4e00\u7aef\uff0c\u7136\u540e\u6e05\u7406\u6389\u7aef\u8fb9\u754c\u5916\u7684\u5185\u5b58\u7a7a\u95f4\u3002<\/p>\n
\u4f18\u70b9\uff1a<\/p>\n
\u89e3\u51b3\u4e86\u5185\u5b58\u788e\u7247\u95ee\u9898\uff0c\u4e0d\u9700\u8981\u590d\u5236\u6d3b\u52a8\u5bf9\u8c61\u3002
\u7f3a\u70b9\uff1a<\/p>\n
\u9700\u8981\u79fb\u52a8\u5b58\u6d3b\u5bf9\u8c61\uff0c\u53ef\u80fd\u4f1a\u9020\u6210\u8f83\u5927\u7684\u5185\u5b58\u8fc1\u79fb\u5f00\u9500\u3002
\u9700\u8981\u8f83\u591a\u7684\u505c\u987f\u65f6\u95f4\uff0c\u4e0d\u9002\u5408\u5bf9\u54cd\u5e94\u65f6\u95f4\u8981\u6c42\u8f83\u9ad8\u7684\u5e94\u7528<\/p>\n<\/li>\n
\u590d\u5236\u7b97\u6cd5\u5c06\u5806\u5185\u5b58\u5206\u4e3a\u4e24\u534a\uff1a\u4e00\u534a\u7528\u4e8e\u5206\u914d\u5185\u5b58\uff0c\u53e6\u4e00\u534a\u5904\u4e8e\u7a7a\u95f2\u72b6\u6001\u3002\u5728\u5783\u573e\u6536\u96c6\u671f\u95f4\uff0c\u5b83\u5c06\u6240\u6709\u6d3b\u52a8\u5bf9\u8c61\u4ece\u5f53\u524d\u7684\u5185\u5b58\u533a\u57df\u590d\u5236\u5230\u53e6\u4e00\u534a\uff0c\u63a5\u7740\u6e05\u9664\u539f\u6709\u7684\u5185\u5b58\u533a\u57df\u4e2d\u7684\u6240\u6709\u5bf9\u8c61\u3002<\/p>\n
\u4f18\u70b9\uff1a<\/p>\n
\u89e3\u51b3\u4e86\u5185\u5b58\u788e\u7247\u95ee\u9898\uff0c\u9002\u5408\u5b58\u6d3b\u5bf9\u8c61\u8f83\u5c11\u573a\u666f\u3002
\u7f3a\u70b9\uff1a<\/p>\n
\u4e0d\u9002\u7528\u4e8e\u5904\u7406\u5b58\u6d3b\u8f83\u591a\u5bf9\u8c61\u7684\u573a\u666f
\u4f1a\u5360\u7528\u53cc\u500d\u5185\u5b58\u7a7a\u95f4<\/p>\n<\/li>\n<\/ol>\n\n\n
\n\n\n
Minor GC\u548cFULL GC\u7684\u533a\u522b<\/h2>\nMinor GC<\/h3>\n
Minor GC\u53c8\u79f0\u4e3aYoung Generation GC\uff0c\u662f\u5728\u5e74\u8f7b\u4ee3\uff08Young Generation\uff09<\/strong>\u4e2d\u53d1\u751f\u7684\u5783\u573e\u56de\u6536\u3002<\/p>\n \u5e74\u8f7b\u4ee3\u901a\u5e38\u5305\u542b\u4e09\u4e2a\u90e8\u5206\uff1a<\/p>\n Eden\u7a7a\u95f4\uff1a\u51e0\u4e4e\u6240\u6709\u65b0\u751f\u6210\u7684\u5bf9\u8c61\u9996\u5148\u90fd\u662f\u5728\u8fd9\u91cc\u5206\u914d\u7684\u3002 \u65b0\u5bf9\u8c61\u88ab\u5206\u914d\u5230Eden\u533a\uff0c\u5f53Eden\u533a\u6ee1\u4e86\u4e4b\u540e\uff0c\u89e6\u53d1Minor GC\u3002 Full GC\uff0c\u53c8\u79f0\u4e3aMajor GC\u6216Old Generation GC\uff0c\u6d89\u53ca\u6574\u4e2aJava\u5806\uff08Heap\uff09\u7684\u56de\u6536\uff0c\u5373\u5305\u62ec\u5e74\u8f7b\u4ee3\u3001\u8001\u5e74\u4ee3\uff08Old Generation\uff09\uff0c\u4ee5\u53ca\u65b9\u6cd5\u533a\uff08\u4e5f\u79f0\u4e3a\u6c38\u4e45\u4ee3\u5728JDK 7\u6216\u4e4b\u524d\u7684\u7248\u672c\uff0c\u6216\u8005\u5143\u7a7a\u95f4\u5728JDK 8\u4ee5\u540e\u7684\u7248\u672c\uff09\u3002<\/strong><\/p>\n Full GC\u7684\u8fc7\u7a0b\u76f8\u5bf9\u6765\u8bf4\u6bd4Minor GC\u8981\u590d\u6742\u4e14\u8017\u65f6\uff1a<\/p>\n \u5bf9\u5e74\u8f7b\u4ee3\u6267\u884cMinor GC\u3002 Minor GC\u548cFull GC\u7684\u89e6\u53d1\u6761\u4ef6\u5404\u4e0d\u76f8\u540c\uff1a<\/p>\n Minor GC\u901a\u5e38\u662f\u5f53\u5e74\u8f7b\u4ee3\u7684Eden\u533a\u6ee1\u4e86\u65f6\u89e6\u53d1\u3002<\/p>\n Full GC\u53ef\u80fd\u7531\u4ee5\u4e0b\u51e0\u4e2a\u6761\u4ef6\u89e6\u53d1\uff1a<\/p>\n \u8001\u5e74\u4ee3\u7a7a\u95f4\u4e0d\u8db3\u3002 \u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565\uff08Promotion Guarantee\uff09\u662fJVM\u4e2d\u7684\u4e00\u79cd\u673a\u5236\uff0c\u786e\u4fdd\u5728Minor GC\u65f6\uff0c\u5b58\u6d3b\u7684\u5bf9\u8c61\u80fd\u591f\u6210\u529f\u664b\u5347\u5230\u8001\u5e74\u4ee3\u3002\u5982\u679c\u8001\u5e74\u4ee3\u6ca1\u6709\u8db3\u591f\u7684\u7a7a\u95f4\u6765\u63a5\u6536\u65b0\u664b\u5347\u7684\u5bf9\u8c61\uff0cJVM\u53ef\u80fd\u4f1a\u63d0\u524d\u89e6\u53d1\u4e00\u6b21Full GC\u6765\u91ca\u653e\u7a7a\u95f4\uff0c\u6216\u8005\u8c03\u6574\u81ea\u5df1\u7684\u5185\u5b58\u5206\u914d\u7b56\u7565\u4ee5\u907f\u514d\u6b64\u7c7b\u60c5\u51b5\u7684\u53d1\u751f\u3002<\/p>\n \u5728\u8fdb\u884cMinor GC\u524d\uff0c\u865a\u62df\u673a\u4f1a\u68c0\u67e5\u8001\u5e74\u4ee3\u6700\u5927\u53ef\u7528\u7684\u8fde\u7eed\u7a7a\u95f4\u662f\u5426\u5927\u4e8e\u65b0\u751f\u4ee3\u6240\u6709\u5bf9\u8c61\u603b\u7a7a\u95f4\u3002\u5982\u679c\u8fd9\u4e2a\u6761\u4ef6\u4e0d\u80fd\u6ee1\u8db3\uff0c\u865a\u62df\u673a\u4f1a\u67e5\u770b -XX:HandlePromotionFailure \u8bbe\u7f6e\u662f\u5426\u5141\u8bb8\u62c5\u4fdd\u5931\u8d25\u3002\u5982\u679c\u4e0d\u5141\u8bb8\uff08false\uff09\uff0c\u90a3\u4e48\u4f1a\u63d0\u524d\u8fdb\u884c\u4e00\u6b21Full GC\u6765\u6e05\u7406\u8001\u5e74\u4ee3\u5e76\u4e3a\u65b0\u751f\u4ee3\u664b\u5347\u7684\u5bf9\u8c61\u817e\u51fa\u7a7a\u95f4\u3002\u5982\u679c\u5141\u8bb8\u62c5\u4fdd\u5931\u8d25\uff08true\uff09\uff0c\u90a3\u4e48\u53ea\u8981\u8001\u5e74\u4ee3\u5269\u4f59\u7a7a\u95f4\u5927\u4e8e\u5386\u6b21\u664b\u5347\u5230\u8001\u5e74\u4ee3\u5bf9\u8c61\u7684\u5e73\u5747\u5927\u5c0f\u5373\u53ef\u8fdb\u884cMinor GC\uff0c\u5426\u5219\u4e5f\u8981\u63d0\u524d\u8fdb\u884cFull GC\u3002<\/p>\n<\/li>\n \u4eceJDK 7\u5f00\u59cb\uff0cHotSpot\u865a\u62df\u673a\u7684\u5783\u573e\u6536\u96c6\u5668\u5728\u505aMinor GC\u4e4b\u524d\u7684\u7a7a\u95f4\u5206\u914d\u62c5\u4fdd\u7b56\u7565\u4e0a\u8fdb\u884c\u4e86\u8c03\u6574\uff0c\u53d6\u6d88\u4e86\u4e4b\u524d\u7248\u672c\u4e2d\u7684 -XX:HandlePromotionFailure \u9009\u9879\u3002\u6bcf\u6b21\u90fd\u4f1a\u5224\u65ad\u8001\u5e74\u4ee3\u5269\u4f59\u6700\u5927\u8fde\u7eed\u7a7a\u95f4\u5927\u4e8e\u5386\u6b21Minor GC\u664b\u5347\u7684\u5e73\u5747\u5927\u5c0f \u6216\u8005 \u5927\u4e8e\u65b0\u751f\u4ee3\u6240\u6709\u5bf9\u8c61\u7684\u5927\u5c0f\u603b\u548c \uff0c \u5927\u4e8e\u4efb\u610f\u4e00\u4e2a\uff0c\u5c31\u5141\u8bb8\u89e6\u53d1MinorGC\uff0c\u53cd\u4e4b\u89e6\u53d1 Full GC \u00a0<\/p>\n<\/li>\n<\/ul>\n \u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565\u7684\u8c03\u4f18\u901a\u5e38\u6d89\u53ca\u51e0\u4e2a\u5173\u952e\u7684JVM\u53c2\u6570\uff1a<\/p>\n -XX:SurvivorRatio: \u8bbe\u7f6e\u65b0\u751f\u4ee3\u4e2dEden\u533a\u4e0eSurvivor\u533a\u7684\u6bd4\u4f8b\u3002 \u5982\u679c\u6ca1\u6709\u7a7a\u95f4\u62c5\u4fdd\uff0cMinor GC\u4f1a\u8fdb\u884c\u5c1d\u8bd5\uff0c\u5f88\u53ef\u80fd\u5728\u664b\u5347\u8fc7\u7a0b\u4e2d\u5931\u8d25\uff0c\u56e0\u4e3a\u8001\u5e74\u4ee3\u6ca1\u6709\u8db3\u591f\u7684\u7a7a\u95f4\u3002\u8fd9\u65f6JVM\u53ef\u80fd\u4f1a\u629b\u51fa OutOfMemoryError\uff0c\u6216\u8005\u5c1d\u8bd5\u4e00\u6b21\u6602\u8d35\u7684Full GC\u6765\u5f3a\u5236\u56de\u6536\u7a7a\u95f4\u3002<\/p>\n \u800c\u5f00\u542f\u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565\uff0cJVM\u5728\u5f00\u59cbMinor GC\u4e4b\u524d\u4f1a\u68c0\u67e5\u8001\u5e74\u4ee3\u662f\u5426\u6709\u8db3\u591f\u7684\u7a7a\u95f4\u3002\u5728\u8fd9\u4e2a\u60c5\u51b5\u4e0b\uff0cJVM\u4f1a\u8ba4\u8bc6\u5230\u8001\u5e74\u4ee3\u7a7a\u95f4\u4e0d\u8db3\uff0c\u56e0\u6b64\u53ef\u80fd\u76f4\u63a5\u89e6\u53d1Full GC\uff0c\u6765\u786e\u4fdd\u4e0d\u4f1a\u5728Minor GC\u8fc7\u7a0b\u4e2d\u51fa\u73b0\u5185\u5b58\u5206\u914d\u5931\u8d25\u3002<\/p>\n \u603b\u4e4b\uff0c\u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565\u662f\u4e00\u79cd\u9884\u9632\u63aa\u65bd\uff0c\u4fdd\u969cJVM\u5728\u8fdb\u884cMinor GC\u65f6\u7684\u5185\u5b58\u5206\u914d\u5b89\u5168\u6027\uff0c\u5c3d\u91cf\u51cf\u5c11Full GC\u7684\u53d1\u751f\uff0c\u4ee5\u63d0\u9ad8\u7cfb\u7edf\u7684\u6027\u80fd\u548c\u7a33\u5b9a\u6027\u3002<\/p>\n \u6ce8\uff1a\u6bcf\u6b21\u7684\u5783\u573e\u56de\u6536\u90fd\u662f\u5bf9\u7cfb\u7edf\u8d44\u6e90\u7684\u4e00\u6b21\u6d88\u8017\uff0c\u56e0\u6b64\u9002\u5f53\u7684\u8c03\u4f18\u53ef\u4ee5\u51cf\u5c11GC\u7684\u6b21\u6570\u548c\u5f71\u54cd\uff0c\u4ece\u800c\u4e3a\u5e94\u7528\u7a0b\u5e8f\u63d0\u4f9b\u66f4\u5e73\u6ed1\u7684\u6027\u80fd\u4f53\u9a8c\u3002<\/p>\n\n\n \u00a0<\/p>\n ZGC\u662f\u4e00\u79cd\u4f4e\u5ef6\u8fdf\u7684\u5783\u573e\u56de\u6536\u5668\uff0c\u76ee\u524d\u4ecd\u5728\u79ef\u6781\u5f00\u53d1\u4e2d\u3002ZGC\u7684\u8bbe\u8ba1\u521d\u8877\u662f\u4e3a\u4e86\u5728\u5927\u5806\u5185\u5b58\u4e0a\u5de5\u4f5c\uff0c\u5e76\u4e14\u51e0\u4e4e\u4e0d\u4ea7\u751f\u5ef6\u8fdf\u3002\u8fd9\u4f7f\u5f97\u5b83\u975e\u5e38\u9002\u5408\u9700\u8981\u5feb\u901f\u54cd\u5e94\u4f46\u662f\u5185\u5b58\u5360\u7528\u5927\u7684\u5e94\u7528\u7a0b\u5e8f\u3002<\/p>\n \u4f7f\u7528\u53c2\u6570\uff1a<\/p>\n -XX:+UseZGC<\/p>\n Shenandoah GC\u4e0eZGC\u6709\u7c7b\u4f3c\u7684\u76ee\u6807\uff1a\u51cf\u5c11\u505c\u987f\u65f6\u95f4\uff0c\u5373\u4fbf\u662f\u5728\u5927\u5806\u6216\u8005\u591a\u6838\u5fc3\u5904\u7406\u5668\u7684\u60c5\u51b5\u4e0b\u3002Shenandoah\u901a\u8fc7\u5728GC\u7684\u8bb8\u591a\u9636\u6bb5\u4e0e\u5e94\u7528\u7ebf\u7a0b\u5e76\u53d1\u6267\u884c\u6765\u5b9e\u73b0\u8fd9\u4e00\u76ee\u6807\u3002<\/p>\n \u4f7f\u7528\u53c2\u6570\uff1a<\/p>\n -XX:+UseShenandoahGC<\/p>\n \u5728\u9009\u62e9\u5783\u573e\u56de\u6536\u5668\u65f6\uff0c\u9700\u8981\u8003\u8651\u5e94\u7528\u7a0b\u5e8f\u7684\u9700\u6c42\uff1a<\/p>\n \u5bf9\u4e8e\u9700\u8981\u6700\u5927\u541e\u5410\u91cf\u7684\u5e94\u7528\u7a0b\u5e8f\uff0cParallel GC\u53ef\u80fd\u662f\u6700\u597d\u7684\u9009\u62e9\u3002 JDK 8\uff08Java Development Kit 8\uff09\u4e2d\u9ed8\u8ba4\u7684\u5783\u573e\u56de\u6536\u5668\u7ec4\u5408\u4e3aParallel Scavenge\uff08\u7528\u4e8eYoung Generation\uff09\u52a0\u4e0aParallel Old\uff08\u7528\u4e8eOld Generation\uff09\u3002Parallel GC \u5728 JDK 5 \u4e2d\u5f00\u59cb\u6210\u4e3a\u9ed8\u8ba4\u7684\u5783\u573e\u56de\u6536\u5668\uff0c\u7279\u70b9\uff1a\u5e76\u884c+STW\u3002<\/p>\n Parallel Scavenge\u6536\u96c6\u5668\u662f\u4e00\u4e2a\u65b0\u751f\u4ee3\u5783\u573e\u6536\u96c6\u5668\uff0c\u5b83\u4f7f\u7528\u590d\u5236\u7b97\u6cd5\uff0c\u800c\u4e14\u662f\u5e76\u884c\u7684\u591a\u7ebf\u7a0b\u6536\u96c6\u5668\u3002\u5b83\u4e3b\u8981\u5173\u6ce8\u4e8e\u8fbe\u5230\u4e00\u4e2a\u53ef\u63a7\u5236\u7684\u541e\u5410\u91cf\uff08Throughput\uff09\u3002\u6240\u8c13\u541e\u5410\u91cf\uff0c\u5c31\u662fCPU\u7528\u4e8e\u8fd0\u884c\u7528\u6237\u4ee3\u7801\u7684\u65f6\u95f4\u4e0eCPU\u603b\u6d88\u8017\u65f6\u95f4\u7684\u6bd4\u503c\uff0c\u5373\uff1a\u541e\u5410\u91cf = \u7528\u6237\u4ee3\u7801\u65f6\u95f4 \/\uff08\u7528\u6237\u4ee3\u7801\u65f6\u95f4 + \u5783\u573e\u6536\u96c6\u65f6\u95f4\uff09\u3002\u670d\u52a1\u5668\u73af\u5883\u4e2d\uff0c\u8fd9\u79cd\u6536\u96c6\u5668\u80fd\u591f\u6700\u5927\u5316\u7684\u5229\u7528CPU\u65f6\u95f4\uff0c\u5c3d\u5feb\u5730\u5b8c\u6210\u7a0b\u5e8f\u7684\u8fd0\u7b97\u4efb\u52a1\uff0c\u7279\u522b\u9002\u7528\u4e8e\u591a\u6838\u670d\u52a1\u5668\u3002<\/p>\n Parallel Old\u6536\u96c6\u5668\u662fParallel Scavenge\u6536\u96c6\u5668\u7684\u8001\u5e74\u4ee3\u7248\u672c\uff0c\u4f7f\u7528\u591a\u7ebf\u7a0b\u548c”\u6807\u8bb0-\u6574\u7406”\u7b97\u6cd5\u3002\u8fd9\u4e2a\u6536\u96c6\u5668\u662f\u5728JDK 6u14\u7248\u4e4b\u540e\u5f15\u5165\u7684\u3002\u4eceJDK 9 \u5f00\u59cb\u9ed8\u8ba4\u5783\u573e\u56de\u6536\u5668\u662f G1 (Garbage-First)<\/p>\n CMS\uff08Concurrent Mark-Sweep\uff09\u6536\u96c6\u5668\u662f\u4e00\u4e2a\u4ee5\u83b7\u53d6\u6700\u77ed\u56de\u6536\u505c\u987f\u65f6\u95f4\u4e3a\u76ee\u6807\u7684\u6536\u96c6\u5668\uff0c\u4f7f\u7528”\u6807\u8bb0-\u6e05\u9664”\u7b97\u6cd5\uff0c\u5e76\u4e14\u662f\u5e76\u53d1\u7684\u3002\u4f46\u662f\u5728JDK\u7248\u672c\u7684\u8fed\u4ee3\u4e2d\u6ca1\u6709\u4efb\u4f55\u4e00\u4e2a\u7248\u672c\u4f7f\u7528CMS\u4e3a\u4e00\u4e2a\u9ed8\u8ba4\u7684\u5783\u573e\u56de\u6536\u5668\u3002<\/p>\n \u9009\u62e9Parallel Scavenge\u548cParallel Old\u7684\u539f\u56e0\u800c\u4e0d\u7528CMS\uff0c\u901a\u5e38\u57fa\u4e8e\u4ee5\u4e0b\u8003\u8651\uff1a<\/p>\n \u541e\u5410\u91cf\u4f18\u5148\uff1a \u5982\u679c\u5e94\u7528\u4e0d\u662f\u975e\u5e38\u6ce8\u91cd\u670d\u52a1\u54cd\u5e94\u65f6\u95f4\uff0c\u800c\u662f\u66f4\u5e0c\u671b\u5728\u5355\u4f4d\u65f6\u95f4\u5185\u5b8c\u6210\u66f4\u591a\u7684\u5de5\u4f5c\uff0c\u5373\u8ffd\u6c42\u8f83\u9ad8\u7684\u541e\u5410\u91cf\uff0c\u90a3\u4e48Parallel Scavenge\u52a0\u4e0aParallel Old\u5783\u573e\u6536\u96c6\u5668\u4f1a\u662f\u4e00\u4e2a\u66f4\u5408\u9002\u7684\u9009\u62e9\u3002<\/p>\n \u788e\u7247\u5316\u95ee\u9898\uff1aCMS\u4f7f\u7528\u7684”\u6807\u8bb0-\u6e05\u9664”\u7b97\u6cd5\u5bb9\u6613\u5bfc\u81f4\u5185\u5b58\u788e\u7247\u5316\uff0c\u5f53\u788e\u7247\u5316\u4e25\u91cd\u5230\u4e00\u5b9a\u7a0b\u5ea6\uff0cCMS\u9700\u8981\u8fdb\u884c\u4e00\u6b21\u5b8c\u5168\u505c\u987f\u7684\u5783\u573e\u6536\u96c6\u4ee5\u6574\u7406\u5185\u5b58\u788e\u7247\uff08Full GC\uff09\uff0c\u8fd9\u53ef\u80fd\u5bfc\u81f4\u8f83\u957f\u65f6\u95f4\u7684\u505c\u987f\u3002\u800cParallel Old\u4f7f\u7528\u7684”\u6807\u8bb0-\u6574\u7406”\u7b97\u6cd5\u53ef\u4ee5\u6709\u6548\u907f\u514d\u5185\u5b58\u788e\u7247\u5316\u95ee\u9898\u3002<\/p>\n \u66f4\u7b80\u5355\u7a33\u5b9a\uff1a \u76f8\u8f83\u4e8eCMS\uff0cParallel Scavenge\u548cParallel Old\u901a\u5e38\u6765\u8bf4\u7ef4\u62a4\u8d77\u6765\u6bd4\u8f83\u7b80\u5355\uff0c\u53c2\u6570\u914d\u7f6e\u4e5f\u66f4\u5bb9\u6613\u3002\u800cCMS\u6709\u51e0\u767e\u4e2a\u53c2\u6570\u9700\u8981\u914d\u7f6e\u8c03\u6574\uff0c\u5bf9\u4e8e\u7ef4\u62a4\u7684\u6210\u672c\u662f\u975e\u5e38\u9ad8\u7684\u3002<\/p>\n \u968f\u7740Java 9\u7684\u53d1\u5e03\uff0cG1\uff08Garbage-First\uff09\u5783\u573e\u6536\u96c6\u5668\u6210\u4e3a\u4e86\u9ed8\u8ba4\u7684\u5783\u573e\u6536\u96c6\u5668\uff0c\u5b83\u65e8\u5728\u66ff\u4ee3CMS\uff0c\u63d0\u4f9b\u66f4\u597d\u7684\u6027\u80fd\u8868\u73b0\u548c\u66f4\u7b80\u5355\u7684\u8c03\u4f18\u9009\u9879\u3002\u800c\u5728Java 11\u4e4b\u540e\uff0c\u8fd8\u5f15\u5165\u4e86ZGC\u548cShenandoah\u7b49\u5b9e\u9a8c\u6027\u7684\u4f4e\u505c\u987f\u65f6\u95f4\u5783\u573e\u6536\u96c6\u5668\u3002<\/p>\n CMS\uff08Concurrent Mark Sweep\uff09\u548cG1\uff08Garbage-First\uff09\u662fJava\u865a\u62df\u673a\u4e2d\u7684\u4e24\u79cd\u4e0d\u540c\u7684\u5783\u573e\u56de\u6536\u5668\uff0c\u5b83\u4eec\u5404\u81ea\u6709\u4e0d\u540c\u7684\u7279\u70b9\u548c\u9002\u7528\u573a\u666f\u3002<\/p>\n 1.CMS\u5783\u573e\u56de\u6536\u6d41\u7a0b<\/strong> <\/p>\n","protected":false},"excerpt":{"rendered":" \u5783\u573e\u5224\u5b9a \u5783\u573e\u5224\u5b9a\u662f\u6307\u5728\u7f16\u7a0b\u4e2d\u786e\u5b9a\u54ea\u4e9b\u5185\u5b58\u4e2d\u7684\u5bf9\u8c61\u662f\u201c\u5783\u573e\u201d\uff0c\u5373\u4e0d\u518d\u88ab\u5e94\u7528\u7a0b\u5e8f\u4f7f\u7528\u7684\u5bf9\u8c61\uff0c\u56e0\u6b64\u53ef\u4ee5\u88ab\u5783\u573e\u56de\u6536\u5668 […]<\/p>\n","protected":false},"author":1,"featured_media":20,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[6],"class_list":["post-259","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized","tag-jvm"],"_links":{"self":[{"href":"http:\/\/www.zackzzp.top\/index.php\/wp-json\/wp\/v2\/posts\/259","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.zackzzp.top\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.zackzzp.top\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.zackzzp.top\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.zackzzp.top\/index.php\/wp-json\/wp\/v2\/comments?post=259"}],"version-history":[{"count":5,"href":"http:\/\/www.zackzzp.top\/index.php\/wp-json\/wp\/v2\/posts\/259\/revisions"}],"predecessor-version":[{"id":268,"href":"http:\/\/www.zackzzp.top\/index.php\/wp-json\/wp\/v2\/posts\/259\/revisions\/268"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.zackzzp.top\/index.php\/wp-json\/wp\/v2\/media\/20"}],"wp:attachment":[{"href":"http:\/\/www.zackzzp.top\/index.php\/wp-json\/wp\/v2\/media?parent=259"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.zackzzp.top\/index.php\/wp-json\/wp\/v2\/categories?post=259"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.zackzzp.top\/index.php\/wp-json\/wp\/v2\/tags?post=259"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\u4e24\u4e2aSurvivor\u7a7a\u95f4\uff08\u901a\u5e38\u79f0\u4e3aFrom\u548cTo\u6216\u8005S0\u548cS1\uff09\uff1a\u7528\u6765\u5b58\u653e\u4eceEden\u548c\u81ea\u5df1\u533a\u57df\u4e2d\u7ecf\u8fc7\u7b2c\u4e00\u6b21Minor
GC\u540e\u4ecd\u7136\u5b58\u6d3b\u7684\u5bf9\u8c61\u3002
Minor GC\u7684\u8fc7\u7a0b\u901a\u5e38\u662f\u8fd9\u6837\u7684\uff1a<\/p>\n
\u5b58\u6d3b\u7684\u5bf9\u8c61\u4eceEden\u533a\u590d\u5236\u5230\u4e00\u4e2aSurvivor\u533a\uff08From\uff09\u3002
\u5982\u679c\u5b58\u5728\u4e4b\u524d\u5df2\u7ecf\u7ecf\u8fc7\u4e00\u6b21Minor GC\u7684\u5bf9\u8c61\uff0c\u5b83\u4eec\u4f1a\u88ab\u4ece\u4e00\u4e2aSurvivor\u533a\u590d\u5236\u5230\u53e6\u4e00\u4e2a\uff08\u4eceFrom\u5230To\uff09\uff0c\u540c\u65f6\u5bf9\u8c61\u7684\u5e74\u9f84\u4f1a\u589e\u52a0\u3002\u5f53\u5bf9\u8c61\u5e74\u9f84\u8fbe\u5230\u4e00\u5b9a\u9608\u503c\u4e4b\u540e\uff0c\u5b83\u4eec\u4f1a\u88ab\u664b\u5347\u5230\u8001\u5e74\u4ee3\uff08Old Generation\uff09\u3002
\u7ecf\u8fc7\u5783\u573e\u56de\u6536\u540e\uff0cEden\u533a\u548c\u4e00\u4e2aSurvivor\u533a\uff08\u4ece\u54ea\u91cc\u590d\u5236\u7684\uff09\u4f1a\u88ab\u6e05\u7a7a\u3002
Minor GC\u7684\u7279\u70b9\u662f\u9891\u7e41\u4e14\u901f\u5ea6\u5feb\u3002\u5b83\u53ea\u662f\u9488\u5bf9\u5e74\u8f7b\u4ee3\u7684\u5783\u573e\u56de\u6536\uff0c\u800c\u4e14\u901a\u5e38\u60c5\u51b5\u4e0b\u53ea\u4f1a\u56de\u6536\u4e00\u5c0f\u90e8\u5206\u5185\u5b58\u7a7a\u95f4\u3002<\/p>\n<\/p>\nFULL\u00a0 GC<\/h3>\n
\u7136\u540e\u8001\u5e74\u4ee3\u7684\u5bf9\u8c61\u4e5f\u4f1a\u88ab\u68c0\u67e5\uff0c\u4e0d\u518d\u5b58\u6d3b\u7684\u5bf9\u8c61\u4f1a\u88ab\u6e05\u9664\u3002
\u65b9\u6cd5\u533a\/\u5143\u7a7a\u95f4\u4e2d\u4e0d\u518d\u4f7f\u7528\u7684\u7c7b\u548c\u9759\u6001\u5185\u5bb9\u5c06\u88ab\u56de\u6536\u3002
\u8bc6\u522b\u8001\u5e74\u4ee3\u4e2d\u53ef\u4ee5\u79fb\u52a8\u7684\u5bf9\u8c61\uff0c\u5e76\u6574\u7406\u5185\u5b58\u7a7a\u95f4\uff0c\u4ece\u800c\u5728\u8001\u5e74\u4ee3\u4e2d\u4e5f\u80fd\u9ad8\u6548\u5730\u5206\u914d\u5185\u5b58\u3002
Full GC\u53d1\u751f\u7684\u65f6\u5019\uff0c\u901a\u5e38\u4f1a\u89e6\u53d1STW\uff08Stop-The-World\uff09\uff0c\u5373\u6240\u6709\u7684\u5e94\u7528\u7ebf\u7a0b\u90fd\u4f1a\u88ab\u6682\u505c\uff0c\u76f4\u5230GC\u5b8c\u6210\u3002<\/p>\n<\/p>\n\u89e6\u53d1\u6761\u4ef6<\/h3>\n
\u65b9\u6cd5\u533a\/\u5143\u7a7a\u95f4\u5185\u5b58\u4e0d\u8db3\u3002
System.gc()\u65b9\u6cd5\u7684\u8c03\u7528\u3002
JVM\u7684\u5185\u5b58\u56de\u6536\u7b56\u7565\u3002<\/p>\n\n\n
\n\n\n\u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565<\/h2>\n
\u5b9a\u4e49<\/h3>\n
\u5de5\u4f5c\u539f\u7406<\/h3>\n
\n
jdk6\u4e4b\u540e \u5c31\u6ca1\u6709\u662f\u5426\u5141\u8bb8\u62c5\u4fdd\u5931\u8d25\u7684\u9009\u9879\u4e86<\/p>\n\u5982\u4f55\u8c03\u4f18\u7a7a\u95f4\u62c5\u4fdd\u7b56\u7565<\/h3>\n
-XX:NewRatio: \u8bbe\u7f6e\u65b0\u751f\u4ee3\u4e0e\u8001\u5e74\u4ee3\u7684\u6bd4\u4f8b\u3002
-XX:MaxTenuringThreshold: \u8bbe\u7f6e\u5bf9\u8c61\u5728\u65b0\u751f\u4ee3\u7684\u5b58\u6d3b\u6b21\u6570\uff0c\u8d85\u8fc7\u8fd9\u4e2a\u6b21\u6570\u7684\u5bf9\u8c61\u4f1a\u88ab\u664b\u5347\u5230\u8001\u5e74\u4ee3\u3002
-XX:PretenureSizeThreshold: \u8bbe\u7f6e\u5927\u5c0f\u9608\u503c\uff0c\u8d85\u8fc7\u8fd9\u4e2a\u5927\u5c0f\u7684\u5bf9\u8c61\u4e0d\u4f1a\u5728\u65b0\u751f\u4ee3\u5206\u914d\uff0c\u800c\u76f4\u63a5\u5728\u8001\u5e74\u4ee3\u5206\u914d\u3002
\u8c03\u4f18\u901a\u5e38\u9700\u8981\u6839\u636e\u5e94\u7528\u7a0b\u5e8f\u7684\u5177\u4f53\u60c5\u51b5\u6765\u8fdb\u884c\u3002\u76d1\u63a7\u5de5\u5177\uff08\u5982jstat, VisualVM\u6216\u5176\u4ed6\u5546\u4e1a\u76d1\u63a7\u5de5\u5177\uff09\u53ef\u4ee5\u5e2e\u52a9\u4f60\u7406\u89e3\u5185\u5b58\u4f7f\u7528\u60c5\u51b5\uff0c\u5e76\u636e\u6b64\u505a\u51fa\u8c03\u6574\u3002<\/p>\n\u603b\u7ed3<\/h3>\n
\n\n\n\n\u5783\u573e\u56de\u6536\u5668<\/h2>\n
Serial GC<\/h3>\n
![\"image\"](\"https:\/\/img.picgo.net\/2024\/10\/01\/imagec6577a9b11596687.png\")
<\/div><\/p>\nParallel GC<\/h3>\n
![\"image\"](\"https:\/\/img.picgo.net\/2024\/10\/01\/image5e97052931323e66.png\")
<\/div><\/p>\nCMS GC<\/h3>\n
![\"image\"](\"https:\/\/img.picgo.net\/2024\/10\/01\/imagee809f7c4b8947f96.png\")
<\/div><\/p>\nG1 GC<\/h3>\n
![\"image\"](\"https:\/\/img.picgo.net\/2024\/10\/01\/image4543e07029b3b511.png\")
<\/div><\/p>\nZ GC<\/h3>\n
Shenandoah GC<\/h3>\n
\u5982\u4f55\u9009\u62e9\u5408\u9002\u7684\u5783\u573e\u5904\u7406\u5668<\/h3>\n
\u5982\u679c\u5e94\u7528\u9700\u8981\u8f83\u77ed\u7684\u54cd\u5e94\u65f6\u95f4\u6216\u8005\u8f83\u5c11\u7684\u505c\u987f\u65f6\u95f4\uff0c\u53ef\u4ee5\u8003\u8651CMS\u6216G1\u3002
\u5bf9\u4e8e\u9700\u8981\u6781\u4f4e\u505c\u987f\u65f6\u95f4\u5e76\u4e14\u5177\u6709\u5927\u5185\u5b58\u5bb9\u91cf\u7684\u5e94\u7528\uff0cZGC\u6216\u8005Shenandoah\u53ef\u80fd\u662f\u5408\u9002\u7684\u9009\u62e9\u3002
\u5728\u5b9e\u9645\u4e2d\uff0c\u6700\u597d\u7684\u65b9\u6cd5\u662f\u901a\u8fc7\u5b9e\u9645\u7684\u6027\u80fd\u6d4b\u8bd5\u6765\u786e\u5b9a\u6700\u9002\u5408\u4f60\u7684\u5e94\u7528\u7684\u5783\u573e\u56de\u6536\u5668\u3002<\/p>\nJDK8\u9ed8\u8ba4\u56de\u6536\u5904\u7406\u5668<\/h3>\n
CMS\u4e0d\u4f5c\u4e3a\u9ed8\u8ba4\u5904\u7406\u5668\u7684\u539f\u56e0<\/h3>\n
CMS\u548cG1\u7684\u6bd4\u8f83<\/h3>\n
\u521d\u59cb\u6807\u8bb0\uff1aGC\u4e3a\u5355\u7ebf\u7a0b\uff0c\u6682\u505c\u6240\u6709\u7528\u6237\u7ebf\u7a0b\uff0c\u53ea\u6807\u8bb0GC Root \u76f4\u63a5\u5f15\u7528\u7684\u5bf9\u53d1\u6807\u8bb0\uff1a\u591a\u4e2aGC\u7ebf\u7a0b\u548c\u7528\u6237\u7ebf\u7a0b\u540c\u65f6\u5de5\u4f5c\uff0c\u4eceGC Roots\u5f00\u59cb\u904d\u5386\u6574\u4e2a\u5bf9\u8c61\u56fe\uff0c\u627e\u51fa\u6240\u6709\u53ef\u8fbe\u5bf9\u8c61\u3002
\u4f7f\u7528\u4e09\u8272\u6807\u8bb0\u6cd5\uff0c\u5bf9\u8c61\u88ab\u5206\u4e3a\u4e09\u79cd\u989c\u8272\uff1a\u767d\u8272\uff08\u672a\u88ab\u626b\u63cf\uff09\u3001\u7070\u8272\uff08\u5df2\u626b\u63cf\u4f46\u5176\u5f15\u7528\u5c1a\u672a\u5168\u90e8\u626b\u63cf\uff09\u3001\u9ed1\u8272\uff08\u5df2\u626b\u63cf\u4e14\u5176\u5f15\u7528\u4e5f\u5df2\u5168\u90e8\u626b\u63cf\uff09\u3002\u521d\u59cb\u65f6\uff0c\u6240\u6709\u5bf9\u8c61\u88ab\u89c6\u4e3a\u767d\u8272\u3002\u968f\u7740\u626b\u63cf\u7684\u8fdb\u884c\uff0c\u5bf9\u8c61\u4ece\u767d\u8272\u53d8\u4e3a\u7070\u8272\uff0c\u7136\u540e\u53d8\u4e3a\u9ed1\u8272\u3002\u6240\u6709\u53ef\u8fbe\u5bf9\u8c61\u6807\u8bb0\u4e3a\u9ed1\u8272\u3002
\u91cd\u65b0\u6807\u8bb0\uff1a\u7531\u4e8e\u5e76\u53d1\u6807\u8bb0\u9636\u6bb5\u7528\u6237\u7a0b\u5e8f\u4ecd\u5728\u8fd0\u884c\uff0c\u53ef\u80fd\u4f1a\u5bfc\u81f4\u90e8\u5206\u5bf9\u8c61\u7684\u6807\u8bb0\u72b6\u6001\u53d1\u751f\u6539\u53d8\uff0c\u91cd\u65b0\u6807\u8bb0\u9636\u6bb5\u5c31\u662f\u4e3a\u4e86\u4fee\u6b63\u8fd9\u4e9b\u53d8\u52a8\u3002
\u591a\u4e2aGC\u7ebf\u7a0bSTW\u8fdb\u884c\u3002
\u5e76\u53d1\u6e05\u7406\uff1a\u591a\u4e2aGC\u7ebf\u7a0b\u5e76\u53d1\u6e05\u7406\u90a3\u4e9b\u5728\u6807\u8bb0\u9636\u6bb5\u88ab\u6807\u8bb0\u4e3a\u5783\u573e\uff08\u5373\u672a\u88ab\u6807\u8bb0\u4e3a\u9ed1\u8272\u7684\u5bf9\u8c61\uff09\u7684\u5bf9\u8c61\uff0c\u91ca\u653e\u5185\u5b58\u7a7a\u95f4\u3002
\u5e76\u53d1\u91cd\u7f6e\uff1a\u591a\u4e2aGC\u7ebf\u7a0b\u5e76\u53d1\u5c06\u5b58\u6d3b\u5bf9\u8c61\u4e0a\u7684\u6807\u8bb0\u7ed9\u79fb\u9664\u6389\uff0c\u907f\u514d\u5f71\u7b49\u4e0b\u6b21gc
2. G1\u5783\u573e\u56de\u6536\u6d41\u7a0b<\/strong>
\u521d\u59cb\u6807\u8bb0:GC\u5355\u7ebf\u7a0b\u8fdb\u884c\u6807\u8bb0\uff0c\u6682\u505c\u6240\u6709\u7528\u6237\u7ebf\u7a0b,\u8bb0\u5f55GC ROOT \u76f4\u63a5\u5f15\u7528\u7684\u5bf9\u8c61
\u5e76\u53d1\u6807\u8bb0:\u591a\u4e2aGC\u7ebf\u7a0b\u548c\u7528\u6237\u7ebf\u7a0b\u540c\u65f6\u5de5\u4f5c\uff0c\u4eceGC Roots\u5f00\u59cb\u904d\u5386\u6574\u4e2a\u5bf9\u8c61\u56fe\uff0c\u627e\u51fa\u6240\u6709\u53ef\u8fbe\u5bf9\u8c61\u3002
\u4f7f\u7528\u4e09\u8272\u6807\u8bb0\u6cd5\uff0c\u5bf9\u8c61\u88ab\u5206\u4e3a\u4e09\u79cd\u989c\u8272\uff1a\u767d\u8272\uff08\u672a\u88ab\u626b\u63cf\uff09\u3001\u7070\u8272\uff08\u5df2\u626b\u63cf\u4f46\u5176\u5f15\u7528\u5c1a\u672a\u5168\u90e8\u626b\u63cf\uff09\u3001\u9ed1\u8272\uff08\u5df2\u626b\u63cf\u4e14\u5176\u5f15\u7528\u4e5f\u5df2\u5168\u90e8\u626b\u63cf\uff09\u3002\u521d\u59cb\u65f6\uff0c\u6240\u6709\u5bf9\u8c61\u88ab\u89c6\u4e3a\u767d\u8272\u3002\u968f\u7740\u626b\u63cf\u7684\u8fdb\u884c\uff0c\u5bf9\u8c61\u4ece\u767d\u8272\u53d8\u4e3a\u7070\u8272\uff0c\u7136\u540e\u53d8\u4e3a\u9ed1\u8272\u3002\u6240\u6709\u53ef\u8fbe\u5bf9\u8c61\u6807\u8bb0\u4e3a\u9ed1\u8272\u3002
\u6700\u7ec8\u6807\u8bb0:\u56e0\u4e3a\u4e0a\u4e2a\u8fc7\u7a0b\u662f\u5e76\u53d1\u8fdb\u884c\u7684,\u6240\u4ee5\u6709\u4e9b\u5bf9\u8c61\u662f\u5728\u6807\u8bb0\u8fc7\u7a0b\u4e2d\u65b0\u4ea7\u751f\u7684,\u5bfc\u81f4\u6ca1\u6709\u6807\u8bb0\u4e0a,\u6240\u4ee5\u8fd9\u4e2a\u8fc7\u7a0b\u8fdb\u884c\u4fee\u6b63\uff0c\u5c06\u8fd9\u4e9b\u6f0f\u7f51\u4e4b\u9c7c\u90fd\u6807\u4e0a\uff0c\u8fd9\u4e2a\u8fc7\u7a0b\u662f\u591a\u7ebf\u7a0b STW \u8fdb\u884c\u3002\u53ef\u4ee5\u901a\u8fc7\u589e\u91cf\u6807\u8bb0\u6216\u4f7f\u7528\u5199\u5c4f\u969c\u6280\u672f\u6765\u51cf\u5c11\u9700\u8981\u91cd\u65b0\u6807\u8bb0\u7684\u5bf9\u8c61\u6570\u91cf\u3002
\u7b5b\u9009\u56de\u6536:\u8ba1\u7b97\u6bcf\u4e2aregion\u7684\u56de\u6536\u6210\u672c\uff0c\u5e76\u6309\u7167\u56de\u6536\u6210\u672c\u8fdb\u884c\u6392\u5e8f\uff0c\u7136\u540e\u6309\u7167\u7528\u6237\u671f\u671b\u7684\u505c\u987f\u65f6\u95f4\u8fdb\u884c\u8ba1\u7b97\uff0c\u51b3\u5b9a\u5e94\u8be5\u56de\u6536\u54ea\u4e9bregion\u3002\u53ef\u4ee5\u901a\u8fc7\u66f4\u667a\u80fd\u7684region\u9009\u62e9\u7b97\u6cd5\u6765\u4f18\u5316\uff0c\u4f8b\u5982\u4f18\u5148\u56de\u6536\u5783\u573e\u5bf9\u8c61\u6700\u591a\u7684region\u6216\u56de\u6536\u6210\u672c\u6700\u4f4e\u7684region\u3002
G1\u6536\u96c6\u5668\u662f\u4e3a\u4e86\u66ff\u4ee3CMS\u6536\u96c6\u5668\u800c\u8bbe\u8ba1\u7684\uff0c\u63d0\u4f9b\u66f4\u53ef\u9884\u6d4b\u7684\u5783\u573e\u56de\u6536\u6682\u505c\u65f6\u95f4\uff0c\u7279\u522b\u662f\u5728\u5904\u7406\u5927\u5185\u5b58\u5bb9\u91cf\u7684\u591a\u5904\u7406\u5668\u673a\u5668\u65f6\u3002G1\u80fd\u591f\u66f4\u597d\u5730\u63a7\u5236\u505c\u987f\u65f6\u95f4\uff0c\u901a\u8fc7\u5c06\u5806\u5206\u5272\u6210\u591a\u4e2a\u533a\u57df\uff08Region\uff09\u6765\u907f\u514d\u6574\u4e2a\u5806\u7684\u5783\u573e\u56de\u6536\uff0c\u9010\u6b65\u5730\u6e05\u7406\u5185\u5b58\uff0c\u7279\u522b\u9002\u5408\u5927\u5806\u5185\u5b58\u7684\u5e94\u7528\u3002
3. \u4e24\u8005\u6bd4\u8f83<\/strong>
\u505c\u987f\u65f6\u95f4\u63a7\u5236\uff1aG1\u5177\u6709\u66f4\u597d\u7684\u505c\u987f\u65f6\u95f4\u63a7\u5236\u80fd\u529b\uff0c\u53ef\u4ee5\u4e3a\u5e94\u7528\u7a0b\u5e8f\u8bbe\u7f6e\u505c\u987f\u65f6\u95f4\u76ee\u6807\u3002
\u5185\u5b58\u5360\u7528\uff1aG1\u901a\u5e38\u6bd4CMS\u9700\u8981\u66f4\u591a\u7684\u5185\u5b58\u7a7a\u95f4\uff0c\u56e0\u4e3a\u5b83\u9700\u8981\u7ef4\u62a4\u66f4\u591a\u7684\u5185\u5b58\u7ed3\u6784\u3002
\u9884\u6d4b\u6027\u80fd\uff1aG1\u53ef\u4ee5\u66f4\u51c6\u786e\u5730\u9884\u6d4b\u5783\u573e\u6536\u96c6\u7684\u505c\u987f\u65f6\u95f4\uff0c\u56e0\u4e3a\u5b83\u662f\u57fa\u4e8e\u533a\u57df\u7684\u56de\u6536\u3002
\u9002\u7528\u573a\u666f\uff1aCMS\u9002\u7528\u4e8e\u5bf9\u54cd\u5e94\u65f6\u95f4\u6bd4\u8f83\u654f\u611f\u7684\u5e94\u7528\u3002\u800cG1\u9002\u7528\u4e8e\u5806\u5185\u5b58\u8f83\u5927\u7684\u573a\u666f\uff0c\u7279\u522b\u662f\u8d85\u8fc74GB\u7684\u5806\u5185\u5b58\u3002
\u968f\u7740Java\u865a\u62df\u673a\u7684\u53d1\u5c55\uff0cG1\u7531\u4e8e\u5176\u66f4\u597d\u7684\u53ef\u9884\u6d4b\u6027\u548c\u9002\u5e94\u6027\uff0c\u8d8a\u6765\u8d8a\u591a\u5730\u6210\u4e3a\u9ed8\u8ba4\u7684\u5783\u573e\u6536\u96c6\u5668\uff0c\u5c24\u5176\u662f\u5728Java 9\u53ca\u4ee5\u540e\u7684\u7248\u672c\u4e2d\u3002<\/p>\n\n\n