{"id":10008229,"date":"2023-09-05T20:16:22","date_gmt":"2023-09-05T12:16:22","guid":{"rendered":"https:\/\/blog.itmax.cn\/?p=10008229"},"modified":"2023-09-05T20:16:22","modified_gmt":"2023-09-05T12:16:22","slug":"jdk17%e4%b8%8bnetty%e5%af%bc%e8%87%b4%e5%a0%86%e5%86%85%e5%ad%98%e7%96%af%e6%b6%a8%e5%8e%9f%e5%9b%a0%e6%8e%92%e6%9f%a5-%e4%ba%ac%e4%b8%9c%e4%ba%91%e6%8a%80%e6%9c%af%e5%9b%a2%e9%98%9f","status":"publish","type":"post","link":"https:\/\/itmax.cn\/?p=10008229","title":{"rendered":"jdk17\u4e0bnetty\u5bfc\u81f4\u5806\u5185\u5b58\u75af\u6da8\u539f\u56e0\u6392\u67e5 | 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20230823174329.png\"><\/p>\n<h4>\u4f4e\u5ef6\u8fdf\u7684\u74f6\u9888<\/h4>\n<p>\u7075\u7391\u7b2c1\u4e2a\u7248\u672c\u7ecf\u8fc7\u5927\u91cf\u4f18\u5316\uff0c\u7cfb\u7edf\u80fd\u63d0\u4f9b\u8f83\u5927\u7684\u541e\u5410\u91cf\u3002\u5982\u679c\u5bf9\u5ba2\u6237\u7aef\u8bbe\u7f6e10ms\u8d85\u65f6\uff0c\u670d\u52a1\u7aef1wqps\/core\u7684\u6d41\u91cf\u4e0b\uff0c\u53ef\u7528\u7387\u53ea\u80fd\u4fdd\u8bc1\u572898.9%\u5de6\u53f3\uff0c\u9ad8\u5e76\u53d1\u60c5\u51b5\u4e0b\u4e3b\u8981\u662fgc\u5bfc\u81f4\u53ef\u7528\u7387\u964d\u4f4e\u3002\u5982\u679c\u57fa\u4e8ecms \u5783\u573e\u56de\u6536\u5668\u3002\u5f53\u4e00\u53f08c16g\u7684\u673a\u5668\u5728\u7ecf\u8fc7\u7b2c\u4e8c\u4e2a\u7248\u672c\u4f18\u5316\u540e\u541e\u5410\u91cf\u8d85\u8fc720wqps\u7684\u65f6\u5019\uff0c\u90a3\u4e48\u5927\u6982\u6bcf4\u79d2\u4f1a\u4ea7\u751f\u4e00\u6b21gc\u3002\u5982\u679c\u6309\u7167\u4e00\u6b21gc\u7b49\u4e8e30ms\u3002\u90a3\u4e48\u81f3\u5c11\u5206\u949f\u9897\u7c92\u5ea6\u5728gc\u65f6\u95f4\u7684\u5360\u6bd4\u81f3\u5c11\u5728(15*30\/1000\/60)=0.0075\u3002\u4e5f\u5c31\u610f\u5473\u7740\u5206\u949f\u7ea7\u522b\u7684tp992\u81f3\u5c11\u572830ms\u3002\u4e0d\u6ee1\u8db3\u76f8\u5173\u4e1a\u52a1\u7684\u9700\u6c42\u3002<\/p>\n<h4>jdk17+ZGC<\/h4>\n<p>\u4e3a\u4e86\u89e3\u51b3\u4e0a\u8ff0\u5ef6\u8fdf\u8fc7\u9ad8\u7684\u76f8\u5173\u95ee\u9898\uff0cJDK 11 \u5f00\u59cb\u63a8\u51fa\u4e86\u4e00\u79cd\u4f4e\u5ef6\u8fdf\u5783\u573e\u56de\u6536\u5668 ZGC\u3002ZGC \u4f7f\u7528\u4e86\u4e00\u4e9b\u65b0\u6280\u672f\u548c\u4f18\u5316\u7b97\u6cd5\uff0c\u53ef\u4ee5\u5c06 GC \u6682\u505c\u65f6\u95f4\u63a7\u5236\u5728 10 \u6beb\u79d2\u4ee5\u5185\uff0c\u800c\u5728 JDK 17 \u7684\u52a0\u6301\u4e0b\uff0cZGC \u7684\u6682\u505c\u65f6\u95f4\u751a\u81f3\u53ef\u4ee5\u63a7\u5236\u5728\u4e9a\u6beb\u79d2\u7ea7\u522b\u3002\u5b9e\u6d4b\u5728\u5e73\u5747\u505c\u987f\u65f6\u95f4\u572810us\u5de6\u53f3\uff0c\u4e3b\u8981\u662f\u57fa\u4e8e\u4e00\u4e2a\u67d3\u8272\u6307\u9488\u548c\u8bfb\u5c4f\u969c\u505a\u5230\u5927\u591a\u6570gc\u9636\u6bb5\u53ef\u4ee5\u505a\u5230\u5e76\u53d1\u7684\uff0c\u6709\u5174\u8da3\u7684\u540c\u5b66\u53ef\u4ee5\u4e86\u89e3\u4e0b\uff0c\u5e76\u4e14jdk17\u662f\u4e00\u4e2alts\u7248\u672c\u3002<\/p>\n<h2>\u95ee\u9898\uff1a<\/h2>\n<p>\u91c7\u7528jdk17+zgc\u7ecf\u8fc7\u76f8\u5173\u7684\u538b\u6d4b\u540e\uff0c\u4e00\u5207\u90fd\u5728\u5411\u7740\u597d\u7684\u65b9\u5411\u53d1\u5c55\uff0c\u4f46\u662f\u5728\u4e00\u79cd\u7279\u6b8a\u573a\u666f\u538b\u6d4b\uff0c\u9700\u8981\u5c06\u6570\u636e\u4ece\u5317\u4eac\u6570\u636e\u4e2d\u5fc3\u540c\u6b65\u7ed9\u5bbf\u8fc1\u6570\u636e\u4e2d\u5fc3\u7684\u65f6\u5019\uff0c\u53d1\u73b0\u4e86\u4e00\u4e9b\u8be1\u5f02\u7684\u4e8b\u60c5<\/p>\n<ul>\n<li>\u670d\u52a1\u7aef\u5bb9\u5668\u7684\u5185\u5b58\u75af\u6da8\uff0c\u5e76\u4e14\u505c\u6b62\u538b\u6d4b\u540e\uff0c\u5185\u5b58\u53ea\u662f\u975e\u5e38\u7f13\u6162\u7684\u51cf\u5c11\u3002<\/li>\n<li>\u76f8\u5173\u673a\u5668cpu\u4e00\u76f4\u4fdd\u5b58\u572820%\uff08\u5df2\u7ecf\u65e0\u6d41\u91cf\u8bf7\u6c42\uff09<\/li>\n<li>\u4e00\u76f4\u5728\u6b21\u6570\u4e0d\u591a\u7684gc\u3002\u5927\u6982\u6bcf10s\u4e00\u6b21<\/li>\n<\/ul>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044182618\" alt=\"Pasted image 20230823101641.png\" title=\"Pasted image 20230823101641.png\" loading=\"lazy\"><\/p>\n<h2>\u6392\u67e5\u4e4b\u65c5<\/h2>\n<h4>\u5185\u5b58\u6cc4\u6f0f\u6392\u67e5<\/h4>\n<p>\u7b2c\u4e00\u53cd\u5e94\u662f\u9047\u5230\u5185\u5b58\u75af\u6da8\u548c\u65e0\u6cd5\u91ca\u653e\u8be5\u95ee\u9898\u65f6\uff0c\u9996\u5148\u5f52\u7eb3\u4e3a\u5185\u5b58\u6cc4\u6f0f\u95ee\u9898\uff0c\u611f\u89c9\u8fd9\u9898\u4e5f\u7b80\u5355\u660e\u4e86\u3002\u5f00\u59cb\u76f8\u5173\u5185\u5b58\u6cc4\u6f0f\u68c0\u67e5\uff1a\u5148dump\u5806\u5185\u5b58\u5206\u6790\u53d1\u73b0\u5360\u7528\u5806\u5185\u5b58\u7684\u662fnetty\u76f8\u5173\u7684\u5bf9\u8c61\uff0c\u6070\u597d\u524d\u6bb5\u65f6\u95f4\u4e5f\u6709\u4e2a\u540c\u5b66\u4e5f\u5206\u4eab\u4e86netty\u4e0b\u7684\u4e0d\u5408\u7406\u4f7f\u7528netty byteBuf\u5bfc\u81f4\u7684\u5185\u5b58\u6cc4\u6f0f\uff0c\u8fdb\u4e00\u6b65\u589e\u52a0\u4e86\u5bf9netty\u5185\u5b58\u6cc4\u9732\u7684\u6000\u7591\u3002 \u4e8e\u662f\u5f00\u542fnetty\u5185\u5b58\u6cc4\u6f0f\u4e25\u683c\u68c0\u67e5\u6a21\u5f0f \uff08\u52a0\u4e0ajvm \u53c2\u6570Dio.netty.leakDetection.level=PARANOID\uff09\uff0c\u91cd\u65b0\u8bd5\u8dd1\u5e76\u6ca1\u6709\u53d1\u73b0\u76f8\u5173\u5185\u5b58\u6cc4\u6f0f\u65e5\u5fd7\u3002\u597d\u5427~\uff01\u521d\u6b65\u5224\u5b9a\u4e0d\u662fnetty\u5185\u5b58\u6cc4\u6f0f\u3002<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044182619\" alt=\"Pasted image 20230823104911.png\" title=\"Pasted image 20230823104911.png\" loading=\"lazy\"><\/p>\n<h4>jdk\u4e0enetty\u7248\u672cbug\u6392\u67e5<\/h4>\n<p>\u4f1a\u4e0d\u4f1a\u662fnetty\u4e0ejdk17\u517c\u5bb9\u4e0d\u597d\u5bfc\u81f4\u7684bug? \u56de\u6edajdk8\u6d4b\u8bd5\u53d1\u73b0\u7684\u786e\u4e0d\u5b58\u5728\u8fd9\u4e2a\u95ee\u9898\uff0c\u5f53\u65f6\u4f7f\u7528\u7684\u662fjdk17.0.7 \u7248\u672c\u3002\u6b63\u597d\u5b98\u65b9\u53d1\u5e03\u4e86jdk17.0.8\u7248\u672c\uff0c\u5e76\u4e14\u770b\u5230\u7248\u672c\u4ecb\u7ecd\u4e0a\u6709\u82e5\u5e72\u7684 Bug Fixes\u3002\u6240\u4ee5\u53c8\u5347\u7ea7\u4e86jdk\u4e00\u4e2a\u5c0f\u7248\u672c\uff0c\u7136\u800c\u53d1\u73b0\u95ee\u9898\u4ecd\u7136\u5728\u3002\u4f1a\u4e0d\u4f1a\u662fnetty\u7684\u7248\u672c\u8fc7\u4f4e\uff1f\u6b63\u597d\u770b\u89c1gitup\u4e0a\u4e5f\u6709\u7c7b\u4f3c\u7684issue# <a target=\"_blank\" href=\"https:\/\/link.segmentfault.com\/?enc=Rkw5zc%2BsnzSWtpW4QKsu5w%3D%3D.6Y8k3E3Sw3%2BESSZWizZOkR2P6Mvq%2F6cyufCdvIkYgNZ11AOXDpYbMQjm3VIN6BDvW1BjKYcQVMHUutqvnYJTNg%3D%3D\" rel=\"noopener noreferrer\">https:\/\/github.com\/netty\/netty\/issues\/6125WriteBufferWaterMark&#8217;s<\/a> \u5e76\u4e14\u5728\u9ad8\u7248\u672c\u7591\u4f3c\u4fee\u590d\u4e86\u8be5\u95ee\u9898\uff0c\u4fee\u6539\u4e86netty\u51e0\u4e2a\u7248\u672c\u91cd\u65b0\u538b\u6d4b\uff0c\u7136\u800c\u53d1\u73b0\u95ee\u9898\u4ecd\u7136\u5728\u3002<\/p>\n<h4>\u76f4\u63a5\u539f\u56e0\u5b9a\u4f4d\u4e0e\u89e3\u51b3<\/h4>\n<p>\u7ecf\u8fc7\u4e0a\u8ff0\u4e24\u6b21\u6392\u67e5\uff0c\u53d1\u73b0\u95ee\u9898\u6bd4\u60f3\u8c61\u4e2d\u590d\u6742\uff0c\u5e94\u8be5\u6df1\u5165\u5206\u6790\u4e0b\u4e3a\u4ec0\u4e48\uff0c\u91cd\u65b0\u68b3\u7406\u4e86\u4e0b\u76f8\u5173\u7ebf\u7d22\uff1a<\/p>\n<ul>\n<li>\u53d1\u73b0\u56de\u6eda\u81f3jdk8\u7684\u65f6\u5019\uff0c\u5bf9\u5e94\u5bbf\u8fc1\u4e2d\u5fc3\u7684\u96c6\u7fa4\u63a5\u53d7\u5230\u7684\u5907\u4efd\u6570\u636e\u91cf\u6bd4\u5317\u4eac\u4e2d\u5fc3\u53d1\u9001\u7684\u6570\u636e\u91cf\u4f4e\u4e86\u5f88\u591a<\/li>\n<li>\u4e3a\u4ec0\u4e48\u6ca1\u6709\u6d41\u91cf\u4e86\u8fd8\u4e00\u76f4\u6709gc\uff0ccpu\u9ad8\u5e94\u8be5\u662fgc\u9020\u6210\u7684\uff08\u5f53\u65f6\u8ba4\u4e3a\u662fzgc\u7684\u5185\u5b58\u7684\u4e00\u4e9b\u7279\u6027\uff09<\/li>\n<li>\u5185\u5b58\u5206\u6790:\u4e3a\u4ec0\u4e48netty\u7684MpscUnboundedArrayQueue\u5f15\u7528\u4e86\u5927\u91cf\u7684AbstractChannelHandlerContext$WriteTask\u5bf9\u8c61\uff0c\u3002MpscUnboundedArrayQueue\u662f\u751f\u4ea7\u6d88\u8d39writeAndFlush\u4efb\u52a1\u961f\u5217\uff0cWriteTask\u662f\u76f8\u5173\u7684writeAndFlush\u7684\u4efb\u52a1\u5bf9\u8c61\uff0c\u6b63\u662f\u56e0\u4e3a\u5927\u91cf\u7684WriteTask\u5bf9\u8c61\u53ca\u5176\u5f15\u7528\u5bfc\u81f4\u4e86\u5185\u5b58\u5360\u7528\u8fc7\u9ad8\u3002<\/li>\n<li>\u53ea\u6709\u8de8\u6570\u636e\u4e2d\u5fc3\u51fa\u73b0\u8be5\u95ee\u9898\uff0c\u540c\u6570\u636e\u4e2d\u5fc3\u6570\u636e\u538b\u6d4b\u4e0d\u4f1a\u51fa\u73b0\u8be5\u95ee\u9898\u3002<\/li>\n<\/ul>\n<p>\u5206\u6790\u8fc7\u540e\u5df2\u7ecf\u6709\u4e86\u57fa\u672c\u7684\u731c\u60f3\uff0c\u56e0\u4e3a\u8de8\u6570\u636e\u4e2d\u5fc3\u4e0b\u673a\u623f\u5ef6\u8fdf\u66f4\u5927\uff0c\u5355channel\u4fe1\u9053\u4e0b\u5df2\u7ecf\u6ca1\u6cd5\u6ee1\u8db3\u540c\u6b65\u6570\u636e\u80fd\u529b\uff0c\u5bfc\u81f4netty\u7684eventLoop\u7684\u6d88\u8d39\u80fd\u4e0d\u8db3\u5bfc\u81f4\u79ef\u538b\u3002<\/p>\n<p>\u89e3\u51b3\u65b9\u6848\uff1a\u589e\u52a0\u4e0e\u5907\u4efd\u6570\u636e\u8282\u70b9\u7684channel\u4fe1\u9053\u8fde\u63a5\uff0c\u91c7\u7528connectionPool\uff0c\u6bcf\u6b21\u6279\u91cf\u540c\u6b65\u6570\u636e\u7684\u65f6\u5019\u968f\u673a\u9009\u62e9\u4e00\u4e2a\u5b58\u6d3b\u7684channel\u8fdb\u884c\u6570\u636e\u901a\u4fe1\u3002\u7ecf\u8fc7\u76f8\u5173\u6539\u9020\u540e\u53d1\u73b0\u95ee\u9898\u5f97\u5230\u4e86\u89e3\u51b3\u3002<\/p>\n<h4>\u6839\u56e0\u5b9a\u4f4d\u4e0e\u89e3\u51b3<\/h4>\n<h5>\u6839\u56e0\u5b9a\u4f4d<\/h5>\n<p>\u867d\u7136\u7ecf\u8fc7\u4e0a\u8ff0\u7684\u6539\u9020\uff0c\u8868\u9762\u4e0a\u770b\u4f3c\u89e3\u51b3\u4e86\u95ee\u9898\uff0c\u4f46\u662f\u95ee\u9898\u7684\u6839\u672c\u539f\u56e0\u8fd8\u662f\u6ca1\u6709\u88ab\u53d1\u73b0<\/p>\n<ul>\n<li>1.\u5982\u679c\u662feventLoop\u6d88\u8d39\u80fd\u529b\u4e0d\u8db3\uff0c\u4e3a\u4ec0\u4e48\u505c\u6b62\u538b\u6d4b\u540e\uff0c\u76f8\u5173\u5185\u5b58\u53ea\u662f\u7f13\u6162\u51cf\u5c11\uff0c\u6309\u7406\u8bf4\u5e94\u8be5\u662f\u75af\u72c2\u7684\u5185\u5b58\u51cf\u5c11\u3002<\/li>\n<li>2.\u4e3a\u4ec0\u4e48\u4e00\u76f4cpu\u572823%\u5de6\u53f3\uff0c\u6309\u7167\u5e73\u65f6\u7684\u538b\u6d4b\u6570\u636e\uff0c\u540c\u6b65\u6570\u636e\u662f\u4e00\u4e2a\u6d41\u8f6c\u6279\u7684\u64cd\u4f5c\uff0c\u6700\u591a\u4e5f\u5c31\u6d88\u80175%cpu \u5de6\u53f3\uff0c\u591a\u51fa\u6765\u7684cpu\u5e94\u8be5\u662fgc\u9020\u6210\u7684\uff0c\u4f46\u662f\u6570\u636e\u540c\u6b65\u5e94\u8be5\u5e76\u4e0d\u591a\uff0c\u4e0d\u5e94\u8be5\u9020\u6210\u8fd9\u4e48\u591a\u7684gc\u538b\u529b\u3002<\/li>\n<li>3.\u4e3a\u4ec0\u4e48jdk8\u4e0b\u4e0d\u4f1a\u5b58\u5728\u8be5\u95ee\u9898<\/li>\n<\/ul>\n<p>\u63a8\u6d4b\u5e94\u8be5\u662f\u6709\u4e2anetty eventLoop\u6d88\u8d39\u8017\u65f6\u963b\u585e\u7684\u64cd\u4f5c\u5bfc\u81f4\u6d88\u8d39\u80fd\u529b\u5927\u5e45\u5ea6\u4e0b\u964d\u3002\u6240\u4ee5\u611f\u89c9\u8fd8\u662fnetty\u7684\u95ee\u9898\uff0c\u4e8e\u662f\u5f00\u4e86netty\u7684\u76f8\u5173debug\u65e5\u5fd7\u3002\u53d1\u73b0\u4e86\u4e00\u884c\u5173\u952e\u65e5\u5fd7<\/p>\n<pre><code>[2023-08-23 11:16:16.163] DEBUG [] - io.netty.util.internal.PlatformDependent0 - direct buffer constructor: unavailable: Reflective setAccessible(true) disabled  \n  \n\n\n<\/code><\/pre>\n<p>\u987a\u7740\u8fd9\u6761\u65e5\u5fd7\u627e\u5230\u4e86\u672c\u6b21\u7684\u95ee\u9898\u6839\u56e0\uff0c\u4e3a\u4ec0\u4e48\u4e00\u4e2a\u76f4\u63a5\u5185\u5b58\u7684\u6784\u9020\u5668\u4e0d\u80fd\u4f7f\u7528\u4f1a\u5bfc\u81f4\u6211\u4eec\u7cfb\u7edfWriteTask\u6d88\u8d39\u963b\u585e\uff0c \u5e26\u7740\u8fd9\u4e2a\u76ee\u7684\u53bb\u67e5\u770b\u76f8\u5173\u7684\u6e90\u7801\u3002<\/p>\n<h5>\u6e90\u7801\u5206\u6790<\/h5>\n<ul>\n<li>\u4e00) netty \u9ed8\u8ba4\u4f1a\u7528PooledByteBufAllocator\u6765\u5206\u914d\u76f4\u63a5\u5185\u5b58\uff0c\u91c7\u7528\u7c7b\u4f3cjmelloc\u7684\u5185\u5b58\u6c60\u673a\u5236\uff0c\u6bcf\u6b21\u5185\u5b58\u4e0d\u8db3\u7684\u65f6\u5019\u4f1a\u901a\u8fc7\u521b\u5efaio.netty.buffer.PoolArena.DirectArena#newChunk\u53bb\u9884\u5360\u7533\u8bf7\u5185\u5b58\u3002<\/li>\n<\/ul>\n<pre><code>  \nprotected PoolChunk&lt;ByteBuffer&gt; newChunk() {  \n     \/\/ \u5173\u952e\u4ee3\u7801  \n        ByteBuffer memory = allocateDirect(chunkSize);  \n    }  \n}  \n\n\n<\/code><\/pre>\n<ul>\n<li>\u4e8c) allocateDirect()\u662f\u7533\u8bf7\u76f4\u63a5\u5185\u5b58\u7684\u903b\u8f91\u3002\u5927\u81f4\u5c31\u662f\u5982\u679c\u80fd\u91c7\u7528\u5e95\u5c42unsafe\u53bb\u7533\u8bf7\u3001\u91ca\u653e\u76f4\u63a5\u5185\u5b58\u548c\u53cd\u5c04\u521b\u5efaByteBuffer\u5bf9\u8c61\uff0c\u90a3\u4e48\u5c31\u91c7\u7528unsafe\u3002\u5426\u5219\u5c31\u76f4\u63a5\u8c03\u7528java\u7684Api ByteBuffer.allocateDirect\u6765\u76f4\u63a5\u5206\u914d\u5185\u5b58\u5e76\u4e14\u91c7\u7528\u81ea\u5e26\u7684Cleaner\u6765\u91ca\u653e\u5185\u5b58\u3002\u8fd9\u91cc PlatformDependent.useDirectBufferNoCleaner \u662f\u4e2a\u5173\u952e\u70b9\uff0c\u5176\u5b9e\u5c31\u662fUSE\/_DIRECT\/_BUFFER\/_NO\/_CLEANER\u53c2\u6570\u914d\u7f6e<\/li>\n<\/ul>\n<pre><code>PlatformDependent.useDirectBufferNoCleaner() ?  \n     PlatformDependent.allocateDirectNoCleaner(capacity) :       ByteBuffer.allocateDirect(capacity);  \n\n\n<\/code><\/pre>\n<ul>\n<li>\n<p>\u4e09) USE\/_DIRECT\/_BUFFER\/_NO\/_CLEANER \u53c2\u6570\u903b\u8f91\u914d\u7f6e\u5728PlatformDependent \u7c7b\u7684static{}\u91cc\u9762\u3002<\/p>\n<p>\u5173\u952e\u903b\u8f91\uff1amaxDirectMemory==0\u548c!hasUnsafe()\u5728jdk17\u4e0b\u6ca1\u6709\u7279\u6b8a\u914d\u7f6e\u90fd\u662f\u4e0d\u6ee1\u8db3\u6761\u4ef6\u7684\uff0c\u5173\u952e\u662fPlatformDependent0.hasDirectBufferNoCleanerConstructor\u7684\u5224\u65ad\u903b\u8f91<\/p>\n<\/li>\n<\/ul>\n<pre><code>if (maxDirectMemory == 0 || !hasUnsafe() || !PlatformDependent0.hasDirectBufferNoCleanerConstructor()) {  \n    USE_DIRECT_BUFFER_NO_CLEANER = false;  \n} else {  \n    USE_DIRECT_BUFFER_NO_CLEANER = true;  \n  \n\n\n<\/code><\/pre>\n<ul>\n<li>\u56db) PlatformDependent0.hasDirectBufferNoCleanerConstructor()\u7684\u5224\u65ad\u662f\u770bPlatformDependent0\u7684DIRECT\/_BUFFER\/_CONSTRUCTOR\u662f\u5426NULL\uff0c\u56de\u5230\u4e86\u521a\u5f00\u7684debug\u65e5\u5fd7\uff0c\u6211\u4eec\u662f\u53ef\u4ee5\u770b\u5230\u5728\u9ed8\u8ba4\u60c5\u51b5\u4e0bDIRECT\/_BUFFER\/_CONSTRUCTOR\u8be5\u6784\u9020\u5668\u662funavailable\u7684\uff08unavailable\u5219\u4e3aNULL\uff09\u3002\u4ee5\u4e0b\u4ee3\u7801\u5177\u4f53\u7684\u903b\u8f91\u5224\u65ad\u53ca\u5176\u4f2a\u4ee3\u7801\u3002<\/li>\n<\/ul>\n<p>1.\u5f00\u542f\u6761\u4ef6\u4e00\uff1ajdk9\u53ca\u5176\u4ee5\u4e0a\u5fc5\u987b\u8981\u5f00\u542fjvm\u53c2\u6570 -io.netty.tryReflectionSetAccessible\u53c2\u6570<\/p>\n<p>2.\u5f00\u542f\u6761\u4ef6\u4e8c\uff1a\u80fd\u53cd\u5c04\u83b7\u53d6\u5230\u4e00\u4e2a private DirectByteBuffer\u6784\u9020\u5668\uff0c\u8be5\u6784\u9020\u5668\u662f\u901a\u8fc7\u5185\u5b58\u5730\u5740\u548c\u5927\u5c0f\u6765\u6784\u9020DirectByteBuffer.\uff08\u5907\u6ce8\uff1a\u5982\u679c\u5728jdk9\u4ee5\u4e0a\u5bf9java.nio\u6709\u6a21\u5757\u6743\u9650\u9650\u5236\uff0c\u9700\u8981\u52a0\u4e0ajvm\u542f\u52a8\u53c2\u6570&#8211;add-opens=java.base\/java.nio=ALL-UNNAMED ,\u5426\u5219\u4f1a\u62a5Unable to make private java.nio.DirectByteBuffer(long,int) accessible: module java.base does not &#8220;opens java.nio&#8221; to unnamed module\uff09<\/p>\n<p>\u6240\u4ee5\u8fd9\u91cc\u6211\u4eec\u9ed8\u8ba4\u662f\u6ca1\u6709\u5f00\u542f\u8fd9\u4e24\u4e2ajvm\u53c2\u6570\u7684\uff0c\u90a3\u4e48DIRECT\/_BUFFER\/_CONSTRUCTOR\u4e3a\u7a7a\u503c\uff0c\u5bf9\u5e94\u7b2c\u4e8c\u90e8PlatformDependent.useDirectBufferNoCleaner()\u4e3afalse\u3002<\/p>\n<pre><code>  \n    \/\/ \u4f2a\u4ee3\u7801\uff0c\u5b9e\u9645\u4e0e\u8fd9\u4e0d\u4e00\u81f4  \n ByteBuffer direct = ByteBuffer.allocateDirect(1);  \n  \n    if(SystemPropertyUtil.getBoolean(&quot;io.netty.tryReflectionSetAccessible&quot;,  \n        javaVersion() &lt; 9 || RUNNING_IN_NATIVE_IMAGE)) {  \n         DIRECT_BUFFER_CONSTRUCTOR =  \n         direct.getClass().getDeclaredConstructor(long.class, int.class)  \n        }  \n\n\n<\/code><\/pre>\n<ul>\n<li>\u4e94) \u73b0\u5728\u56de\u5230\u7b2c2\u6b65\u9aa4\uff0c\u53d1\u73b0PlatformDependent.useDirectBufferNoCleaner()\u5728jdk\u9ad8\u7248\u672c\u4e0b\u9ed8\u8ba4\u503c\u662ffalse\u3002\u90a3\u4e48\u6bcf\u6b21\u7533\u8bf7\u76f4\u63a5\u5185\u5b58\u90fd\u662f\u901a\u8fc7ByteBuffer.allocateDirect\u6765\u521b\u5efa\u3002\u90a3\u4e48\u5230\u8fd9\u4e2a\u65f6\u5019\u5c31\u5df2\u7ecf<strong>\u5b9a\u4f4d<\/strong>\u5230\u76f8\u5173\u6839\u56e0\u4e86\uff0c\u901a\u8fc7ByteBuffer.allocateDirect\u6765\u7533\u8bf7\u76f4\u63a5\u5185\u5b58\uff0c\u5982\u679c\u5185\u5b58\u4e0d\u8db3\u7684\u65f6\u5019\u4f1a\u5f3a\u5236\u7cfb\u7edfSystem.Gc()\uff0c\u5e76\u4e14\u4f1a\u540c\u6b65\u7b49\u5f85DirectByteBuffer\u901a\u8fc7Cleaner\u7684\u865a\u5f15\u7528\u56de\u6536\u5185\u5b58\u3002\u4e0b\u9762\u662fByteBuffer.allocateDirect\u9884\u5360\u5185\u5b58\uff08reserveMemory\uff09\u7684\u5173\u952e\u4ee3\u7801\u3002\u5927\u6982\u903b\u8f91\u662f \u89e6\u8fbe\u7533\u8bf7\u7684\u6700\u5927\u7684\u76f4\u63a5\u5185\u5b58-&gt;\u5224\u65ad\u662f\u5426\u6709\u76f8\u5173\u7684\u5bf9\u8c61\u5728gc\u56de\u6536-&gt;\u6ca1\u6709\u5728\u56de\u6536\u5219\u4e3b\u52a8\u89e6\u53d1System.gc()\u6765\u89e6\u53d1\u56de\u6536-&gt;\u5728\u540c\u6b65\u5faa\u73af\u6700\u591a\u7b49\u5f85MAX_SLEEPS\u6b21\u6570\u770b\u662f\u5426\u6709\u8db3\u591f\u7684\u76f4\u63a5\u5185\u5b58\u3002\u6574\u4e2a\u540c\u6b65\u7b49\u5f85\u903b\u8f91\u5728\u4eb2\u6d4b\u5728jdk17\u7248\u672c\u6700\u591a\u80fd1\u79d2\u4ee5\u4e0a\u3002<\/li>\n<\/ul>\n<p>\u6240\u4ee5\u6700\u6839\u672c\u539f\u56e0\uff1a<strong>\u5982\u679c\u8fd9\u4e2a\u65f6\u5019\u6211\u4eec\u7684netty\u7684\u6d88\u8d39\u8005EventLoop\u5904\u7406\u6d88\u8d39\u56e0\u4e3a\u7533\u8bf7\u76f4\u63a5\u5185\u5b58\u5728\u8fbe\u5230\u6700\u5927\u5185\u5b58\u7684\u573a\u666f\uff0c\u90a3\u4e48\u5c31\u4f1a\u5bfc\u81f4\u6709\u5927\u91cf\u7684\u4efb\u52a1\u6d88\u8d39\u90fd\u4f1a\u540c\u6b65\u53bb\u7b49\u5f85\u7533\u8bf7\u76f4\u63a5\u5185\u5b58\u4e0a\u3002\u5e76\u4e14\u5982\u679c\u6ca1\u6709\u8db3\u591f\u7684\u7684\u76f4\u63a5\u5185\u5b58\uff0c\u90a3\u4e48\u5c31\u4f1a\u6210\u4e3a\u5927\u9762\u79ef\u7684\u6d88\u8d39\u963b\u585e\u3002<\/strong><\/p>\n<pre><code>  \nstatic void reserveMemory(long size, long cap) {  \n  \n    if (!MEMORY_LIMIT_SET &amp;&amp; VM.initLevel() &gt;= 1) {  \n        MAX_MEMORY = VM.maxDirectMemory();  \n        MEMORY_LIMIT_SET = true;  \n    }  \n  \n    \/\/ optimist!  \n    if (tryReserveMemory(size, cap)) {  \n        return;  \n    }  \n  \n    final JavaLangRefAccess jlra = SharedSecrets.getJavaLangRefAccess();  \n    boolean interrupted = false;  \n    try {  \n  \n        do {  \n            try {  \n                refprocActive = jlra.waitForReferenceProcessing();  \n            } catch (InterruptedException e) {  \n                \/\/ Defer interrupts and keep trying.  \n                interrupted = true;  \n                refprocActive = true;  \n            }  \n            if (tryReserveMemory(size, cap)) {  \n                return;  \n            }  \n        } while (refprocActive);  \n  \n        \/\/ trigger VM's Reference processing  \n        System.gc();  \n  \n        int sleeps = 0;  \n        while (true) {  \n            if (tryReserveMemory(size, cap)) {  \n                return;  \n            }  \n            if (sleeps &gt;= MAX_SLEEPS) {  \n                break;  \n            }  \n            try {  \n                if (!jlra.waitForReferenceProcessing()) {  \n                    Thread.sleep(sleepTime);  \n                    sleepTime &lt;&lt;= 1;  \n                    sleeps++;  \n                }  \n            } catch (InterruptedException e) {  \n                interrupted = true;  \n            }  \n        }  \n  \n        \/\/ no luck  \n        throw new OutOfMemoryError  \n            (&quot;Cannot reserve &quot;  \n             + size + &quot; bytes of direct buffer memory (allocated: &quot;  \n             + RESERVED_MEMORY.get() + &quot;, limit: &quot; + MAX_MEMORY +&quot;)&quot;);  \n  \n    } finally {  \n        if (interrupted) {  \n            \/\/ don't swallow interrupts  \n            Thread.currentThread().interrupt();  \n        }  \n    }  \n}  \n\n\n<\/code><\/pre>\n<ul>\n<li>\u516d) \u867d\u7136\u6211\u4eec\u770b\u5230\u4e86\u963b\u585e\u7684\u539f\u56e0\uff0c\u4f46\u662f\u4e3a\u4ec0\u4e48jdk8\u4e0b\u4e3a\u4ec0\u4e48\u5c31<strong>\u4e0d\u4f1a\u963b\u585e<\/strong>\u4ece4\u6b65\u9aa4\u4e2d\u770b\u5230java 9\u4ee5\u4e0b\u662f\u8bbe\u7f6e\u4e86DIRECT\/_BUFFER\/_CONSTRUCTOR\u7684\uff0c\u56e0\u6b64\u91c7\u7528\u7684\u662fPlatformDependent.allocateDirectNoCleaner\u8fdb\u884c\u5185\u5b58\u5206\u914d\u3002 \u4ee5\u4e0b\u662f\u5177\u4f53\u7684\u4ecb\u7ecd\u548c\u5173\u952e\u4ee3\u7801<\/li>\n<\/ul>\n<p>\u6b65\u9aa4\u4e00\uff1a\u7533\u8bf7\u5185\u5b58\u524d\uff1a\u901a\u8fc7\u5168\u5c40\u5185\u5b58\u8ba1\u6570\u5668<strong>DIRECT\/_MEMORY\/_COUNTER<\/strong>\uff0c\u5728\u6bcf\u6b21\u7533\u8bf7\u5185\u5b58\u7684\u65f6\u5019\u8c03\u7528incrementMemoryCounter \u589e\u52a0\u76f8\u5173\u7684size\uff0c\u5982\u679c\u8fbe\u5230\u76f8\u5173DIRECT\/_MEMORY\/_LIMIT(\u9ed8\u8ba4\u662f-XX:MaxDirectMemorySize) \u53c2\u6570\u5219<strong>\u76f4\u63a5\u629b\u51fa\u5f02\u5e38<\/strong>\uff0c\u800c\u4e0d\u4f1a\u53bb\u540c\u6b65gc\u7b49\u5f85\u5bfc\u81f4\u5927\u91cf\u8017\u65f6\u3002\u3002<\/p>\n<p>\u6b65\u9aa4\u4e8c\uff1a<strong>\u5206\u914d\u5185\u5b58allocateDirectNoCleaner<\/strong>:\u662f\u901a\u8fc7unsafe\u53bb\u7533\u8bf7\u5185\u5b58\uff0c\u518d\u7528\u6784\u9020\u5668<strong>DIRECT\/_BUFFER\/_CONSTRUCTOR<\/strong>\u901a\u8fc7\u5185\u5b58\u5730\u5740\u548c\u5927\u5c0f\u6765\u6784\u9020DirectBuffer\u3002\u91ca\u653e\u4e5f\u53ef\u4ee5\u901a\u8fc7unsafe.freeMemory\u6839\u636e\u5185\u5b58\u5730\u5740\u6765\u91ca\u653e\u76f8\u5173\u5185\u5b58\uff0c\u800c\u4e0d\u662f\u901a\u8fc7java \u81ea\u5e26\u7684cleaner\u6765\u91ca\u653e\u5185\u5b58\u3002<\/p>\n<pre><code>public static ByteBuffer allocateDirectNoCleaner(int capacity) {  \n    assert USE_DIRECT_BUFFER_NO_CLEANER;  \n  \n    incrementMemoryCounter(capacity);  \n    try {  \n        return PlatformDependent0.allocateDirectNoCleaner(capacity);  \n    } catch (Throwable e) {  \n        decrementMemoryCounter(capacity);  \n        throwException(e);  \n        return null;    }  \n}  \n  \nprivate static void incrementMemoryCounter(int capacity) {  \n    if (DIRECT_MEMORY_COUNTER != null) {  \n        long newUsedMemory = DIRECT_MEMORY_COUNTER.addAndGet(capacity);  \n        if (newUsedMemory &gt; DIRECT_MEMORY_LIMIT) {  \n            DIRECT_MEMORY_COUNTER.addAndGet(-capacity);  \n            throw new OutOfDirectMemoryError(&quot;failed to allocate &quot; + capacity  \n                    + &quot; byte(s) of direct memory (used: &quot; + (newUsedMemory - capacity)  \n                    + &quot;, max: &quot; + DIRECT_MEMORY_LIMIT + ')');  \n        }  \n    }  \n}  \n  \nstatic ByteBuffer allocateDirectNoCleaner(int capacity) {  \n  return newDirectBuffer(UNSAFE.allocateMemory(Math.max(1, capacity)), capacity);  \n}  \n  \n\n\n<\/code><\/pre>\n<ul>\n<li>\u7ecf\u8fc7\u4e0a\u8ff0\u7684\u6e90\u7801\u5206\u6790\uff0c\u5df2\u7ecf\u770b\u5230\u4e86\u6839\u672c\u539f\u56e0\uff0c\u5c31\u662fByteBuffer.allocateDirect gc \u540c\u6b65\u7b49\u5f85\u76f4\u63a5\u5185\u5b58\u91ca\u653e\u5bfc\u81f4\u6d88\u8d39\u80fd\u529b\u4e25\u91cd\u4e0d\u8db3\u5bfc\u81f4\u7684\uff0c\u5e76\u4e14\u5728\u6700\u5927\u76f4\u63a5\u5185\u5b58\u4e0d\u8db3\u7684\u60c5\u51b5\u4e0b\uff0c\u5927\u9762\u79ef\u7684\u6d88\u8d39\u963b\u585e\u8017\u65f6\u5728\u7533\u8bf7\u76f4\u63a5\u5185\u5b58\uff0c\u5bfc\u81f4\u6d88\u8d39WriteTask\u80fd\u529b\u63a5\u8fd1\u4e8e0\uff0c\u5185\u5b58\u4ece\u800c\u65e0\u6cd5\u4e0b\u964d<\/li>\n<\/ul>\n<h2>\u603b\u7ed3<\/h2>\n<p>1.\u6d41\u7a0b\u56fe\uff1a<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044182620\" alt=\"Pasted image 20230823144106.png\" title=\"Pasted image 20230823144106.png\" loading=\"lazy\"><\/p>\n<p>2.\u76f4\u63a5\u539f\u56e0\uff1a<\/p>\n<ul>\n<li>\u8de8\u6570\u636e\u4e2d\u5fc3\u540c\u6b65\u6570\u636e\u5355channel\u7ba1\u9053\u540c\u6b65\u6570\u636e\u80fd\u529b\u4e0d\u8db3\uff0c\u5bfc\u81f4tcp\u73af\u963b\u585e\u3002\u4ece\u800c\u5bfc\u81f4netty eventLoop\u7684\u6d88\u8d39WriteTask\u4efb\u52a1(WriteAndFlush)\u4e2d\u7684write\u80fd\u529b\u5927\u4e8eflush\u80fd\u529b\uff0c\u56e0\u6b64\u7533\u8bf7\u7684\u5927\u91cf\u7684<strong>\u76f4\u63a5\u5185\u5b58<\/strong>\u5b58\u653e\u5728ChannelOutboundBuffer#unflushedEntry\u94fe\u8868\u4e2d\u6ca1\u6cd5flush\u3002<\/li>\n<\/ul>\n<p>3.\u6839\u672c\u539f\u56e0\uff1a<\/p>\n<ul>\n<li>netty\u5728jdk\u9ad8\u7248\u672c\u9700\u8981\u624b\u52a8\u6dfb\u52a0jvm\u53c2\u6570 -add-opens=java.base\/java.nio=ALL-UNNAMED\u548c-io.netty.tryReflectionSetAccessible \u6765\u5f00\u542f\u91c7\u7528\u76f4\u63a5\u8c03\u7528\u5e95\u5c42unsafe\u6765\u7533\u8bf7\u5185\u5b58\uff0c\u5982\u679c\u4e0d\u5f00\u542f\u90a3\u4e48netty\u7533\u8bf7\u5185\u5b58\u91c7\u7528ByteBuffer.allocateDirect\u6765\u7533\u8bf7\u76f4\u63a5\u5185\u5b58\uff0c\u5982\u679cEventLoop\u6d88\u8d39\u4efb\u52a1\u7533\u8bf7\u7684\u76f4\u63a5\u5185\u5b58\u8fbe\u5230\u6700\u5927\u76f4\u63a5\u5185\u5b58\u573a\u666f\uff0c\u90a3\u4e48\u5c31\u4f1a\u5bfc\u81f4\u6709\u5927\u91cf\u7684\u4efb\u52a1\u6d88\u8d39\u90fd\u4f1a\u540c\u6b65\u53bb\u7b49\u5f85\u7533\u8bf7\u76f4\u63a5\u5185\u5b58\u4e0a\u3002\u5e76\u4e14\u5982\u679c\u6ca1\u6709\u91ca\u653e\u8db3\u591f\u7684\u76f4\u63a5\u5185\u5b58\uff0c\u90a3\u4e48\u5c31\u4f1a\u6210\u4e3a\u5927\u9762\u79ef\u7684\u6d88\u8d39\u963b\u585e\uff0c\u4e5f\u540c\u65f6\u5bfc\u81f4\u5927\u91cf\u7684\u5bf9\u8c61\u7d2f\u79ef\u5728netty\u7684\u65e0\u754c\u961f\u5217MpscUnboundedArrayQueue\u4e2d\u3002<\/li>\n<\/ul>\n<p>4.\u53cd\u601d\u4e0e\u5b9a\u4f4d\u95ee\u9898\u6162\u7684\u539f\u56e0\uff1a<\/p>\n<ul>\n<li>\u9ed8\u8ba4\u540c\u6b65\u6570\u636e\u8fd9\u91cc\u4e0d\u4f1a\u662f\u7cfb\u7edf\u74f6\u9888\uff0c\u6ca1\u6709\u52a0\u4e0alowWaterMark\u548chighWaterMark\u6c34\u4f4d\u7ebf\u7684\u5224\u65ad\uff08socketChannel.isWritable()\uff09\uff0c\u5982\u679c\u540c\u6b65\u6570\u636e\u8fbe\u5230\u7cfb\u7edf\u74f6\u9888\u5e94\u8be5\u63d0\u524d\u80fd\u611f\u77e5\u5230\u629b\u51fa\u5f02\u5e38\u3002<\/li>\n<li>\u540c\u6b65\u6570\u636e\u7684\u65f6\u5019\u8c03\u7528writeAndFlush\u5e94\u8be5\u52a0\u4e0a\u76f8\u5173\u7684\u5f02\u5e38\u76d1\u542c\u5668\uff08\u4ee5\u4e0b\u4ee3\u78012\uff09\uff0c\u82e5\u679c\u80fd\u63d0\u524d\u611f\u77e5\u5230\u5f02\u5e38OutOfMemoryError\u90a3\u4e48\u66f4\u65b9\u4fbf\u6392\u67e5\u5230\u76f8\u5173\u95ee\u9898\u3002<\/li>\n<\/ul>\n<pre><code>\uff081\uff09ChannelFuture writeAndFlush(Object msg)  \n\uff082\uff09ChannelFuture writeAndFlush(Object msg, ChannelPromise promise);  \n\n\n<\/code><\/pre>\n<ul>\n<li>jdk17\u4e0b\u76d1\u63a7\u7cfb\u7edf\u770b\u5230\u7684<strong>\u975e\u5806\u5185\u5b58\u76d1\u63a7<\/strong>\u5e76\u672a\u4e0e<strong>\u7cfb\u7edf\u5b9e\u9645\u4f7f\u7528\u7684\u76f4\u63a5\u5185\u5b58<\/strong>\u7edf\u8ba1\u4e00\u81f4\uff0c\u5bfc\u81f4\u5f00\u59cb\u5b9a\u4f4d\u95ee\u9898\u65e0\u6cd5\u5b9a\u4f4d\u5230\u76f4\u63a5\u5185\u5b58\u5df2\u7ecf\u8fbe\u5230\u6700\u5927\u503c\uff0c\u4ece\u800c\u5e76\u672a\u5f80\u8fd9\u4e2a\u65b9\u6848\u601d\u8003\u3002<\/li>\n<li>\u76f8\u5173\u5f15\u7528\u7684<strong>\u4e2d\u95f4\u4ef6\u5e95\u5c42\u901a\u4fe1\u4e5f\u662f\u4f9d\u8d56\u4e8enetty\u901a\u4fe1<\/strong>\uff0c\u5982\u679c\u6709\u7c7b\u4f3c\u7684\u6570\u636e\u540c\u6b65\u4e5f\u53ef\u80fd\u4f1a\u89e6\u53d1\u7c7b\u4f3c\u7684\u95ee\u9898\u3002\u7279\u522bump\u5728\u9ad8\u7248\u672c\u548ctitan\u4f7f\u7528netty\u7684\u65f6\u5019\u662f\u8fdb\u884c\u4e86shade\u6253\u5305\u7684\uff0c\u5e76\u4e14\u76f8\u5173\u7684jvm\u53c2\u6570\u4e5f\u88ab\u4fee\u6539\uff0c\u867d\u7136\u4e0d\u4f1a\u89e6\u53d1\u8be5bug\uff0c\u4f46\u662f\u4e5f\u53ef\u80fd\u5bfc\u81f4\u89e6\u53d1\u7cfb\u7edfgc\u3002<\/li>\n<\/ul>\n<pre><code>ump\u9ad8\u7248\u672c\uff1ajvm\u53c2\u6570\u4fee\u6539\uff08\u4f4e\u7248\u672c\u76f4\u63a5\u91c7\u7528\u4e86\u5e95\u5c42socket\u901a\u4fe1\uff0c\u672a\u4f7f\u7528netty\u548c\u521b\u5efaByteBuffer\uff09 io.netty.tryReflectionSetAccessible-&gt;ump.profiler.shade.io.netty.tryReflectionSetAccessible  \n  \ntitan\uff1ajvm\u53c2\u6570\u4fee\u6539:io.netty.tryReflectionSetAccessible-&gt;titan.profiler.shade.io.netty.tryReflectionSetAccessible  \n\n<\/code><\/pre>\n<blockquote>\n<p>\u4f5c\u8005\uff1a\u4eac\u4e1c\u96f6\u552e\u00a0\u5218\u9e4f<\/p>\n<p>\u6765\u6e90\uff1a\u4eac\u4e1c\u4e91\u5f00\u53d1\u8005\u793e\u533a \u8f6c\u8f7d\u8bf7\u6ce8\u660e\u6765\u6e90<\/p>\n<\/blockquote>\n<p><a href=\"https:\/\/segmentfault.com\/a\/1190000044182614\">https:\/\/segmentfault.com\/a\/1190000044182614<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u80cc\u666f\uff1a \u4ecb\u7ecd \u5929\u7f51\u98ce\u63a7\u7075\u7391\u7cfb\u7edf\u662f\u57fa\u4e8e\u5185\u5b58\u8ba1\u7b97\u5b9e\u73b0\u7684\u9ad8\u541e\u5410\u4f4e\u5ef6\u8fdf\u5728\u7ebf\u8ba1\u7b97\u670d\u52a1\uff0c\u63d0\u4f9b\u6ed1\u52a8\u6216\u6eda\u52a8\u7a97\u53e3\u5185\u7684count\u3001 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[4],"tags":[],"class_list":["post-10008229","post","type-post","status-publish","format-standard","hentry","category-share"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/posts\/10008229","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=10008229"}],"version-history":[{"count":0,"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/posts\/10008229\/revisions"}],"wp:attachment":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=10008229"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=10008229"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=10008229"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}