{"id":7408,"date":"2022-08-30T11:44:08","date_gmt":"2022-08-30T03:44:08","guid":{"rendered":"https:\/\/egonlin.com\/?p=7408"},"modified":"2022-10-27T10:05:27","modified_gmt":"2022-10-27T02:05:27","slug":"02-fio%e7%a3%81%e7%9b%98%e6%80%a7%e8%83%bd%e6%b5%8b%e8%af%95","status":"publish","type":"post","link":"https:\/\/egonlin.com\/?p=7408","title":{"rendered":"02 \u5bb9\u5668\u6027\u80fd\u6d4b\u8bd5\u4e0e\u5206\u6790\u5de5\u5177"},"content":{"rendered":"<h1>\u4e00 \u5bb9\u5668\u5171\u4eab\u5bbf\u4e3b\u673a\u5185\u6838\u5e26\u6765\u7684\u5f71\u54cd<\/h1>\n<p>\u5bb9\u5668\u91cc\u7684\u8fdb\u7a0b\u5f52\u6839\u7ed3\u5e95\u90fd\u662f\u8fd0\u884c\u5728\u5bbf\u4e3b\u673a\u4e0a\u7684\u8fdb\u7a0b\uff0c\u6240\u4ee5\u5bbf\u4e3b\u673a\u4e00\u65e6\u51fa\u73b0\u6027\u80fd\u95ee\u9898\uff0c\u5b83\u4e0a\u9762\u5bc4\u751f\u7684\u6240\u6709\u7684\u5bb9\u5668\u7684\u6027\u80fd\u90fd\u4f1a\u53d7\u5230\u5f71\u54cd\u3002<\/p>\n<p>\u6bd4\u5982\u5f53\u5bbf\u4e3b\u673a\u5185\u6838\u4eceubuntu 18.04\uff08linux\u5185\u68384.15\uff09\u5347\u7ea7\u5230ubuntu20.04(linux\u5185\u68385.4)\u4e4b\u540e\uff0c\u4f60\u4f1a\u53d1\u73b0\u8be5\u5bbf\u4e3b\u673a\u4e0a\u7684\u5bb9\u5668\u78c1\u76d8io\u8bfb\u5199\u6027\u80fd\u964d\u4f4e\u4e3aubuntu 18.04\u5185\u6838\u76841\/8\u5de6\u53f3\u3002\u56e0\u4e3a\u5bb9\u5668\u91cc\u7684\u201c\u64cd\u4f5c\u7cfb\u7edf\u201d\u53ea\u6709\u4e00\u4e2arootfs\uff0c\u6ca1\u6709bootfs\uff0c\u540c\u4e00\u4e2a\u5bbf\u4e3b\u673a\u4e0a\u7684\u591a\u4e2a\u5bb9\u5668\uff0c\u5927\u5bb6\u662f\u5171\u4eab\u5bbf\u4e3b\u673a\u5185\u6838\u7684\uff0c\u6240\u4ee5\u4e00\u65e6\u5bbf\u4e3b\u673a\u5185\u6838\u6709\u95ee\u9898\uff0c\u4f1a\u76f4\u63a5\u5f71\u54cd\u5230\u5bb9\u5668\u3002<\/p>\n<p>\u5f53\u51fa\u73b0I\/O\u6027\u80fd\u95ee\u9898\u65f6\uff0c\u4e3a\u4e86\u80fd\u591f\u53ca\u65f6\u51c6\u786e\u5730\u5b9a\u4f4d\u5230\u95ee\u9898\uff0c\u53ef\u4ee5\u4f7f\u7528fio\u6765\u6d4b\u8bd5\u4e00\u4e0b\u5bbf\u4e3b\u673a\u6216\u5bb9\u5668\u5185\u7684I\/O\u6027\u80fd\uff0c\u6216\u8005\u4f7f\u7528perf+flameGraph\u6765\u5236\u4f5c\u706b\u7130\u56fe\u6765\u8fdb\u4e00\u6b65\u5206\u6790\u6027\u80fd\u95ee\u9898<\/p>\n<h1>\u4e8c fio\u5de5\u5177<\/h1>\n<p>\u7bc7\u5e45\u8fc7\u957f\uff0c\u8be6\u89c1\uff1a<a href=\"https:\/\/egonlin.com\/?p=250\">https:\/\/egonlin.com\/?p=250<\/a><\/p>\n<h1>\u4e09 perf\u6027\u80fd\u5206\u6790\u5de5\u5177<\/h1>\n<h2>3.1 perf\u5de5\u5177\u4ecb\u7ecd\u4e0e\u57fa\u672c\u4f7f\u7528<\/h2>\n<p>perf\u662f\u4e00\u6b3eLinux\u6027\u80fd\u5206\u6790\u5de5\u5177\u3002<br \/>\n\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528perf\u5de5\u5177\u6765\u6355\u83b7\u4e00\u4e2a\u4efb\u52a1\u5728\u7cfb\u7edf\u4e2d\u7684\u5b8c\u6574\u8c03\u5ea6\u6808\u4fe1\u606f\uff0c\u6216\u8005\u7cfb\u7edf\u6574\u4f53\u7684\u60c5\u51b5\uff0c\u4ee5\u4fbf\u5206\u8bb8\u5230\u5e95\u662f\u54ea\u4e2a\u73af\u8282\u62d6\u6162\u4e86\u6574\u4f53\u7684\u6027\u80fd\u3002<br \/>\n\u4f8b\u5982:<br \/>\n\u5982\u679c\u6211\u4eec\u53d1\u73b0CPU\u7684\u4f7f\u7528\u7387\u7a81\u7136\u66b4\u6da8\uff0c\u5982\u4f55\u8fc5\u901f\u5b9a\u4f4d\u662f\u54ea\u4e2a\u8fdb\u7a0b\u3001\u54ea\u6bb5\u4ee3\u7801\u5f15\u8d77\u7684\u5462\uff1f\u6b64\u65f6\u5c31\u53ef\u4ee5\u7528perf\u5de5\u5177\uff0c\u6765\u5bf9CPU\u4e0a\u6267\u884c\u7684\u4ee3\u7801\u8fdb\u884c\u91c7\u6837\u3001\u7edf\u8ba1\uff0c\u544a\u8bc9\u6211\u4eecCPU\u5230\u5e95\u5728\u5fd9\u4e9b\u4ec0\u4e48\u3002<\/p>\n<p>\u9996\u5148\u6211\u4eec\u7528\u4ee5\u4e0b\u547d\u4ee4\u6a21\u62df\u51faCPU\u5229\u7528\u7387\u66b4\u6da8\u7684\u73b0\u8c61\uff1a<br \/>\n$ cat \/dev\/zero &gt; \/dev\/null<\/p>\n<p>\u7136\u540e\u6211\u4eec\u770b\u5230 CPU 1 \u7684 %system \u98d9\u5347\u523095%\uff1a<\/p>\n<pre><code># sar -P ALL -u 2 2\n08:21:16 PM     CPU     %user     %nice   %system   %iowait    %steal     %idle\n08:21:18 PM     all      2.25      0.00     48.25      0.00      0.00     49.50\n08:21:18 PM       0      0.50      0.00      1.00      0.00      0.00     98.51\n08:21:18 PM       1      4.02      0.00     95.98      0.00      0.00      0.00<\/code><\/pre>\n<p>\u73b0\u5728\u6211\u4eec\u7528 perf \u5de5\u5177\u91c7\u6837\uff1a<\/p>\n<pre><code>\u5b89\u88c5\nyum install perf -y\n\nperf record -a -e cycles -o cycle.perf -g sleep 10\n\n# \u6ce8\u610f\nperf record\u4ee3\u8868\u8bb0\u5f55\u4e00\u6bb5\u65f6\u95f4\u5185\u7cfb\u7edf\/\u8fdb\u7a0b\u7684\u6027\u80fd\u65f6\u95f4\n\u53c2\u6570\uff1a\n -a\uff1a\u5206\u6790\u6574\u4e2a\u7cfb\u7edf\u7684\u6027\u80fd\n -e\uff1a\u9009\u62e9\u6027\u80fd\u4e8b\u4ef6\n -o\uff1a\u6307\u5b9a\u8f93\u51fa\u6587\u4ef6\uff0c\u9ed8\u8ba4\u4e3aperf.data\n -g\uff1a\u8bb0\u5f55\u51fd\u6570\u95f4\u7684\u8c03\u7528\u5173\u7cfb\n sleep 10 \u8868\u793a\u6536\u96c610\u79d2\u949f\u3002<\/code><\/pre>\n<p>\u628a\u91c7\u6837\u7684\u6570\u636e\u751f\u6210\u62a5\u544a\uff1a<\/p>\n<pre><code># perf report -i cycle.perf | less\n\n...\n# Samples: 40K of event &#039;cycles&#039;\n# Event count (approx.): 18491174032\n#\n# Overhead          Command                   Shared Object              Symbol\n# ........  ...............  ..............................    ................\n#\n    75.65%              cat  [kernel.kallsyms]                 [k] __clear_user                     \n                        |\n                        --- __clear_user\n                           |          \n                           |--99.56%-- read_zero\n                           |          vfs_read\n                           |          sys_read\n                           |          system_call_fastpath\n                           |          __GI___libc_read\n                            --0.44%-- [...]\n\n     2.34%              cat  [kernel.kallsyms]                 [k] system_call                      \n                        |\n                        --- system_call\n                           |          \n                           |--56.72%-- __write_nocancel\n                           |          \n                            --43.28%-- __GI___libc_read\n...\n\u6211\u4eec\u5f88\u6e05\u695a\u5730\u770b\u5230\uff0cCPU\u5229\u7528\u7387\u670975%\u6765\u81ea cat \u8fdb\u7a0b \u7684 sys_read \u7cfb\u7edf\u8c03\u7528\uff0c\nperf \u751a\u81f3\u7cbe\u786e\u5730\u544a\u8bc9\u4e86\u6211\u4eec\u662f\u6d88\u8017\u5728 read_zero \u8fd9\u4e2a kernel routine \u4e0a\u3002<\/code><\/pre>\n<h2>3.2 perf\u76f8\u5173\u547d\u4ee4\u4e0e\u53c2\u6570<\/h2>\n<pre><code>-----------------&gt;1\u3001Perf List\n\u6027\u80fd\u4e8b\u4ef6\u662f\u6307\u5728\u5904\u7406\u5668\u6216\u64cd\u4f5c\u7cfb\u7edf\u4e2d\u53d1\u751f\u7684\uff0c\u53ef\u80fd\u5f71\u54cd\u5230\u7a0b\u5e8f\u6027\u80fd\u7684\u786c\u4ef6\u4e8b\u4ef6\u6216\u8f6f\u4ef6\u4e8b\u4ef6\n\u5229\u7528perf\u5256\u6790\u7a0b\u5e8f\u6027\u80fd\u65f6\uff0c\u9700\u8981\u6307\u5b9a\u5f53\u524d\u6d4b\u8bd5\u7684\u6027\u80fd\u4e8b\u4ef6\u3002\n\n\u6211\u4eec\u53ef\u4ee5\u7528perf list\u67e5\u770b\u5f53\u524d\u7cfb\u7edf\u652f\u6301\u7684\u6027\u80fd\u4e8b\u4ef6\n\n\u67e5\u770b\u56fe\u7247\u5305\u542b\u4e86\u8f6f\u4ef6\u4e8b\u4ef6\u4e0e\u786c\u4ef6\u4e8b\u4ef6\uff1a\nhttps:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/3-2.png\nsw\u5b9e\u9645\u4e0a\u662f\u5185\u6838\u7684\u8ba1\u6570\u5668\uff0c\u4e0e\u786c\u4ef6\u65e0\u5173\u3002\nhw\u548ccache\u662fCPU\u67b6\u6784\u76f8\u5173\u7684\uff0c\u4f9d\u8d56\u4e8e\u5177\u4f53\u786c\u4ef6\u3002\ntracepoint\u662f\u57fa\u4e8e\u5185\u6838\u7684ftrace\uff0c\u4e3b\u7ebf2.6.3x\u4ee5\u4e0a\u7684\u5185\u6838\u7248\u672c\u624d\u652f\u6301\u3002\n-----------------&gt;2\u3001Perf top\n\u4e3b\u8981\u7528\u4e8e\u5b9e\u65f6\u5206\u6790\u5404\u4e2a\u51fd\u6570\u5728\u67d0\u4e2a\u6027\u80fd\u4e8b\u4ef6\u4e0a\u7684\u70ed\u5ea6\uff0c\u80fd\u591f\u5feb\u901f\u7684\u5b9a\u4f4d\u70ed\u70b9\u51fd\u6570\uff0c\u5305\u62ec\u5e94\u7528\u7a0b\u5e8f\u51fd\u6570\u3001\n\n\u5e38\u7528\u53c2\u6570\n\n-e\uff1a\u6307\u5b9a\u6027\u80fd\u4e8b\u4ef6\uff0c\u9ed8\u8ba4\u7684\u6027\u80fd\u4e8b\u4ef6\u4e3acpu cycles\u3002\n\n-a\uff1a\u663e\u793a\u5728\u6240\u6709CPU\u4e0a\u7684\u6027\u80fd\u7edf\u8ba1\u4fe1\u606f\n\n-C\uff1a\u663e\u793a\u5728\u6307\u5b9aCPU\u4e0a\u7684\u6027\u80fd\u7edf\u8ba1\u4fe1\u606f\n\n-p\uff1a\u6307\u5b9a\u8fdb\u7a0bPID\n\n-t\uff1a\u6307\u5b9a\u7ebf\u7a0bTID\n\n-K\uff1a\u9690\u85cf\u5185\u6838\u7edf\u8ba1\u4fe1\u606f\n\n-U\uff1a\u9690\u85cf\u7528\u6237\u7a7a\u95f4\u7684\u7edf\u8ba1\u4fe1\u606f\n\n-s\uff1a\u6307\u5b9a\u5f85\u89e3\u6790\u7684\u7b26\u53f7\u4fe1\u606f\n\n\u2018\u2010G\u2019 or\u2018\u2010\u2010call\u2010graph\u2019 &lt;output_type,min_percent,call_order&gt;\n\ngraph: \u4f7f\u7528\u8c03\u7528\u6811\uff0c\u5c06\u6bcf\u6761\u8c03\u7528\u8def\u5f84\u8fdb\u4e00\u6b65\u6298\u53e0\u3002\u8fd9\u79cd\u663e\u793a\u65b9\u5f0f\u66f4\u52a0\u76f4\u89c2\u3002\n\n\u6bcf\u6761\u8c03\u7528\u8def\u5f84\u7684\u91c7\u6837\u7387\u4e3a\u7edd\u5bf9\u503c\u3002\u4e5f\u5c31\u662f\u8be5\u6761\u8def\u5f84\u5360\u6574\u4e2a\u91c7\u6837\u57df\u7684\u6bd4\u7387\u3002\n\nfractal\n\n\u9ed8\u8ba4\u9009\u9879\u3002\u7c7b\u4f3c\u4e0e graph\uff0c\u4f46\u662f\u6bcf\u6761\u8def\u5f84\u524d\u7684\u91c7\u6837\u7387\u4e3a\u76f8\u5bf9\u503c\u3002\n\nflat\n\n\u4e0d\u6298\u53e0\u5404\u6761\u8c03\u7528\n\n\u9009\u9879 call_order \u7528\u4ee5\u8bbe\u5b9a\u8c03\u7528\u56fe\u8c31\u7684\u663e\u793a\u987a\u5e8f\uff0c\u8be5\u9009\u9879\u6709 2\u4e2a\u53d6\u503c\uff0c\u5206\u522b\u662f\n\ncallee \u4e0ecaller\u3002\n\n\u5c06\u8be5\u9009\u9879\u8bbe\u4e3acallee \u65f6\uff0cperf\u6309\u7167\u88ab\u8c03\u7528\u7684\u987a\u5e8f\u663e\u793a\u8c03\u7528\u56fe\u8c31\uff0c\u4e0a\u5c42\u51fd\u6570\u88ab\u4e0b\u5c42\u51fd\u6570\u6240\u8c03\u7528\u3002\n\n\u8be5\u9009\u9879\u88ab\u8bbe\u4e3acaller \u65f6\uff0c\u6309\u7167\u8c03\u7528\u987a\u5e8f\u663e\u793a\u8c03\u7528\u56fe\u8c31\uff0c\u5373\u4e0a\u5c42\u51fd\u6570\u8c03\u7528\u4e86\u4e0b\u5c42\u51fd\u6570\u8def\u5f84\uff0c\u4e5f\u4e0d\u663e\u793a\u6bcf\u6761\u8c03\u7528\u8def\u5f84\u7684\u91c7\u6837\u7387\n\u6ce8\uff1a Perf top\u9700\u8981root\u6743\u9650\n\n\u5217\u540d            \u542b\u4e49\nOverhead        \u7b26\u53f7\u5f15\u53d1\u7684\u6027\u80fd\u4e8b\u4ef6\u6bd4\u4f8b\nShared Object   \u7b26\u53f7\u6240\u5728\u7684DSO(Dynamic Shared Object)\uff0c\u53ef\u4ee5\u662f\u5e94\u7528\u7a0b\u5e8f\u3001\u5185\u6838\u3001\u52a8\u6001\u94fe\u63a5\u5e93\u3001\u6a21\u5757\u3002\nSymbol        \u7b26\u53f7\u540d\uff0c\u524d\u9762\u7684 [ ] \u8868\u793aDSO\u7c7b\u578b\uff0c[.]\u8868\u793a\u6b64\u7b26\u53f7\u5c5e\u4e8e\u7528\u6237\u6001\u7684ELF\u6587\u4ef6\uff0c\u5305\u62ec\u53ef\u6267\u884c\u6587\u4ef6\u4e0e\u52a8\u6001\u94fe\u63a5\u5e93\uff0c[k]\u8868\u8ff0\u6b64\u7b26\u53f7\u5c5e\u4e8e\u5185\u6838\u6216\u6a21\u5757\n\n-----------------&gt;3\u3001Perf stat\n\u5206\u6790\u7cfb\u7edf\/\u8fdb\u7a0b\u7684\u6574\u4f53\u6027\u80fd\u6982\u51b5\n\ntask\u2010clock\u4e8b\u4ef6\u8868\u793a\u76ee\u6807\u4efb\u52a1\u771f\u6b63\u5360\u7528\u5904\u7406\u5668\u7684\u65f6\u95f4\uff0c\u5355\u4f4d\u662f\u6beb\u79d2\u3002\u4e5f\u79f0\u4efb\u52a1\u6267\u884c\u65f6\u95f4\n\ncontext-switches\u662f\u7cfb\u7edf\u53d1\u751f\u4e0a\u4e0b\u6587\u5207\u6362\u7684\u6b21\u6570\n\nCPU-migrations\u662f\u4efb\u52a1\u4ece\u4e00\u4e2a\u5904\u7406\u5668\u8fc1\u5f80\u53e6\u5916\u4e00\u4e2a\u5904\u7406\u5668\u7684\u6b21\u6570\n\npage-faults\u662f\u5185\u6838\u53d1\u751f\u7f3a\u9875\u7684\u6b21\u6570\n\ncycles\u662f\u7a0b\u5e8f\u6d88\u8017\u7684\u5904\u7406\u5668\u5468\u671f\u6570\n\ninstructions\u662f\u6307\u547d\u4ee4\u6267\u884c\u671f\u95f4\u4ea7\u751f\u7684\u5904\u7406\u5668\u6307\u4ee4\u6570\n\nbranches\u662f\u6307\u7a0b\u5e8f\u5728\u6267\u884c\u671f\u95f4\u9047\u5230\u7684\u5206\u652f\u6307\u4ee4\u6570\u3002\n\nbranch\u2010misses\u662f\u9884\u6d4b\u9519\u8bef\u7684\u5206\u652f\u6307\u4ee4\u6570\u3002\n\nXXX seconds time elapsed\u7cfb\u7a0b\u5e8f\u6301\u7eed\u65f6\u95f4\n\n\u4efb\u52a1\u6267\u884c\u65f6\u95f4\/\u4efb\u52a1\u6301\u7eed\u65f6\u95f4\u5927\u4e8e1\uff0c\u90a3\u53ef\u4ee5\u80af\u5b9a\u662f\u591a\u6838\u5f15\u8d77\u7684\n\n\u53c2\u6570\u8bbe\u7f6e\uff1a\n\n-e\uff1a\u9009\u62e9\u6027\u80fd\u4e8b\u4ef6\n\n-i\uff1a\u7981\u6b62\u5b50\u4efb\u52a1\u7ee7\u627f\u7236\u4efb\u52a1\u7684\u6027\u80fd\u8ba1\u6570\u5668\u3002\n\n-r\uff1a\u91cd\u590d\u6267\u884c n \u6b21\u76ee\u6807\u7a0b\u5e8f\uff0c\u5e76\u7ed9\u51fa\u6027\u80fd\u6307\u6807\u5728n \u6b21\u6267\u884c\u4e2d\u7684\u53d8\u5316\u8303\u56f4\u3002\n\n-n\uff1a\u4ec5\u8f93\u51fa\u76ee\u6807\u7a0b\u5e8f\u7684\u6267\u884c\u65f6\u95f4\uff0c\u800c\u4e0d\u5f00\u542f\u4efb\u4f55\u6027\u80fd\u8ba1\u6570\u5668\u3002\n\n-a\uff1a\u6307\u5b9a\u5168\u90e8cpu\n\n-C\uff1a\u6307\u5b9a\u67d0\u4e2acpu\n\n-A\uff1a\u5c06\u7ed9\u51fa\u6bcf\u4e2a\u5904\u7406\u5668\u4e0a\u76f8\u5e94\u7684\u4fe1\u606f\u3002\n\n-p\uff1a\u6307\u5b9a\u5f85\u5206\u6790\u7684\u8fdb\u7a0bid\n\n-t\uff1a\u6307\u5b9a\u5f85\u5206\u6790\u7684\u7ebf\u7a0bid\n\n-----------------&gt;4\u3001Perf record\nperf record\u6536\u96c6\u4e00\u6bb5\u65f6\u95f4\u5185\u7cfb\u7edf\/\u8fdb\u7a0b\u7684\u6027\u80fd\u65f6\u95f4\uff0c\u5e76\u8bb0\u5f55\u5728\u6587\u4ef6\u4e2d\uff0c\u53ef\u4ee5\u79bb\u7ebf\u5206\u6790\u3002\u53ef\u4ee5\u4f7f\u7528 perf report\u89e3\u6790\u6536\u96c6\u7684\u91c7\u6837\u6570\u636e\u6587\u4ef6\u3002\n\u53c2\u6570\uff1a\n\n -e\uff1a\u9009\u62e9\u6027\u80fd\u4e8b\u4ef6\n\n -p\uff1a\u5f85\u5206\u6790\u8fdb\u7a0b\u7684id\n\n -t\uff1a\u5f85\u5206\u6790\u7ebf\u7a0b\u7684id\n\n -a\uff1a\u5206\u6790\u6574\u4e2a\u7cfb\u7edf\u7684\u6027\u80fd\n\n -C\uff1a\u53ea\u91c7\u96c6\u6307\u5b9aCPU\u6570\u636e\n\n -c\uff1a\u4e8b\u4ef6\u7684\u91c7\u6837\u5468\u671f\n\n -o\uff1a\u6307\u5b9a\u8f93\u51fa\u6587\u4ef6\uff0c\u9ed8\u8ba4\u4e3aperf.data\n\n -A\uff1a\u4ee5append\u7684\u65b9\u5f0f\u5199\u8f93\u51fa\u6587\u4ef6\n\n -f\uff1a\u4ee5OverWrite\u7684\u65b9\u5f0f\u5199\u8f93\u51fa\u6587\u4ef6\n\n -g\uff1a\u8bb0\u5f55\u51fd\u6570\u95f4\u7684\u8c03\u7528\u5173\u7cfb\n -F\uff1a\u63a7\u5236perf\u547d\u4ee4\u5bf9cpu\u7684\u5360\u7528\u9891\u7387\uff0c\u5e95\u5c42\u63a7\u5236\u7684\u662f\u5185\u6838\u53c2\u6570perf_event_max_sample_rate\n  \u8be6\u7ec6\u89e3\u6790\uff1a\n  \u5728\/proc\/sys\/kernel\/\u4e0b\u6709\u4e24\u4e2a\u8ddfperf\u76f8\u5173\u7684\u5185\u6838\u53c2\u6570\n \uff081\uff09perf_cpu_time_max_percent  perf\u5206\u6790\u5de5\u5177\u6700\u5927\u80fd\u591f\u5360\u7528CPU\u6027\u80fd\u7684\u767e\u5206\u6bd4\n    0\uff1a\u4e0d\u9650\u5236\n    1~100\uff1a\u767e\u5206\u6bd4\u503c\n \uff082\uff09perf_event_max_sample_rate\uff1a \u8bbe\u7f6eperf_event\u7684\u6700\u5927\u53d6\u6837\u901f\u7387\uff0c\u9ed8\u8ba4\u503c\u4e3a100000\n\n  perf\u547d\u4ee4\u91c7\u6837\u65f6\u4f1a\u5360\u7528cpu\uff0c\u9700\u8981\u5bf9perf\u547d\u4ee4\u5bf9cpu\u7684\u5360\u6bd4\u8fdb\u884c\u9650\u5236\uff0c\n  \u9ed8\u8ba4\u9650\u5236\u6700\u5927\u5c31\u662fperf_cpu_time_max_percent=25\uff0c\u8d85\u8fc7\u8be5\u503c\u5c31\u4f1a\u89e6\u53d1\u544a\u8b66\u5982\u4e0b\n  perf: interrupt took too long (3136 &gt; 3126), lowering kernel.perf_event_max_sample_rate to 63000\n  \u89e6\u53d1\u544a\u8b66\u7684\u540c\u65f6\u4f1a\u8c03\u6574\u91c7\u6837\u901f\u7387perf_event_max_sample_rate\uff0c\u4fdd\u6301\u4e0d\u8981\u8d85\u8fc7\u9650\u5236\u3002\n  \u4e5f\u5c31\u662f\u8bf4\uff0c\u5982\u679c\u4f60\u8bbe\u7f6e\u4e86perf_event_max_sample_rate\uff0c\n  \u90a3\u4e48\u51fa\u73b0\u4e0a\u9762\u8fd9\u4e2a\u544a\u8b66\u540e\uff0cperf_event_max_sample_rate\u7684\u503c\u4f1a\u88ab\u8c03\u6574\u3002\n  \u53ef\u4ee5\u901a\u8fc7\u8c03\u9ad8perf_cpu_time_max_percent\u6765\u89e3\u51b3\u3002\n  \u5982\u679c\u8c03\u9ad8\u4e5f\u4e0d\u80fd\u89e3\u51b3\uff0c\u5c31\u8bbe\u7f6e\u4e3a0\uff0c\u6b64\u65f6\u5c31\u4e0d\u4f1a\u5728\u53bb\u76d1\u63a7cpu\u7684\u5360\u7528\u7387\u4e86\u3002\n  echo 0 &gt; \/proc\/sys\/kernel\/perf_cpu_time_max_percent\n  echo 10000 &gt;  \/proc\/sys\/kernel\/perf_event_max_sample_rate\n\n-----------------&gt;5\u3001Perf Report\nperf report \u4e3b\u8981\u7528\u6765\u5c55\u793a\u4e0a\u9762perf record\u751f\u6210\u7684perf.data\u6587\u4ef6\u3002\n\n\u53c2\u6570\n\n-i\uff1a\u8f93\u5165\u7684\u6570\u636e\u6587\u4ef6\n\n-v\uff1a\u663e\u793a\u6bcf\u4e2a\u7b26\u53f7\u7684\u5730\u5740\n\n-d &lt;dos&gt;\uff1a\u53ea\u663e\u793a\u6307\u5b9ados\u7684\u7b26\u53f7\n\n-C\uff1a\u53ea\u663e\u793a\u6307\u5b9acomm\u7684\u4fe1\u606f\uff08Comm. \u89e6\u53d1\u4e8b\u4ef6\u7684\u8fdb\u7a0b\u540d\uff09\n\n-S\uff1a\u53ea\u8003\u8651\u6307\u5b9a\u7b26\u53f7\n\n-U\uff1a\u53ea\u663e\u793a\u5df2\u89e3\u6790\u7684\u7b26\u53f7\n\n-g[type,min,order]\uff1a\u663e\u793a\u8c03\u7528\u5173\u7cfb\uff0c\u5177\u4f53\u7b49\u540c\u4e8eperf top\u547d\u4ee4\u4e2d\u7684-g\n\n-c\uff1a\u53ea\u663e\u793a\u6307\u5b9acpu\u91c7\u6837\u4fe1\u606f\n\n-M\uff1a\u4ee5\u6307\u5b9a\u6c47\u7f16\u6307\u4ee4\u98ce\u683c\u663e\u793a\n\n\u2013source\uff1a\u4ee5\u6c47\u7f16\u548csource\u7684\u5f62\u5f0f\u8fdb\u884c\u663e\u793a\n\n-p&lt;regex&gt;\uff1a\u7528\u6307\u5b9a\u6b63\u5219\u8868\u8fbe\u5f0f\u8fc7\u6ee4\u8c03\u7528\u51fd\u6570<\/code><\/pre>\n<p>\u4e3e\u4f8b1<\/p>\n<pre><code># perf top -e cycles:k     #\u663e\u793a\u5185\u6838\u548c\u6a21\u5757\u4e2d\uff0c\u6d88\u8017\u6700\u591aCPU\u5468\u671f\u7684\u51fd\u6570\n\n# perf top -e kmem:kmem_cache_alloc     #\u663e\u793a\u5206\u914d\u9ad8\u901f\u7f13\u5b58\u6700\u591a\u7684\u51fd\u6570\n\n# perf top\n\nSamples: 1M of event &#039;cycles&#039;, Event count (approx.): 73891391490\n     5.44%  perf              [.] 0x0000000000023256      \n     4.86%  [kernel]          [k] _spin_lock              \n     2.43%  [kernel]          [k] _spin_lock_bh           \n     2.29%  [kernel]          [k] _spin_lock_irqsave      \n     1.77%  [kernel]          [k] __d_lookup              \n     1.55%  libc-2.12.so      [.] __strcmp_sse42          \n     1.43%  nginx             [.] ngx_vslprintf           \n     1.37%  [kernel]          [k] tcp_poll          \n\n\u7b2c\u4e00\u5217\uff1a\u7b26\u53f7\u5f15\u53d1\u7684\u6027\u80fd\u4e8b\u4ef6\u7684\u6bd4\u4f8b\uff0c\u9ed8\u8ba4\u6307\u5360\u7528\u7684cpu\u5468\u671f\u6bd4\u4f8b\u3002\n\u7b2c\u4e8c\u5217\uff1a\u7b26\u53f7\u6240\u5728\u7684DSO(Dynamic Shared Object)\uff0c\u53ef\u4ee5\u662f\u5e94\u7528\u7a0b\u5e8f\u3001\u5185\u6838\u3001\u52a8\u6001\u94fe\u63a5\u5e93\u3001\u6a21\u5757\u3002\n\u7b2c\u4e09\u5217\uff1aDSO\u7684\u7c7b\u578b\u3002[.]\u8868\u793a\u6b64\u7b26\u53f7\u5c5e\u4e8e\u7528\u6237\u6001\u7684ELF\u6587\u4ef6\uff0c\u5305\u62ec\u53ef\u6267\u884c\u6587\u4ef6\u4e0e\u52a8\u6001\u94fe\u63a5\u5e93)\u3002[k]\u8868\u8ff0\u6b64\u7b26\u53f7\u5c5e\u4e8e\u5185\u6838\u6216\u6a21\u5757\u3002\n\u7b2c\u56db\u5217\uff1a\u7b26\u53f7\u540d\u3002\u6709\u4e9b\u7b26\u53f7\u4e0d\u80fd\u89e3\u6790\u4e3a\u51fd\u6570\u540d\uff0c\u53ea\u80fd\u7528\u5730\u5740\u8868\u793a\u3002<\/code><\/pre>\n<p>\u4e3e\u4f8b2<\/p>\n<pre><code># perf top -g         #\u5f97\u5230\u8c03\u7528\u5173\u7cfb\u56fe\n\n# perf top -e cycles         #\u6307\u5b9a\u6027\u80fd\u4e8b\u4ef6\n\n# perf top -p 23015,32476         #\u67e5\u770b\u8fd9\u4e24\u4e2a\u8fdb\u7a0b\u7684cpu cycles\u4f7f\u7528\u60c5\u51b5\n\n# perf top -s comm,pid,symbol         #\u663e\u793a\u8c03\u7528symbol\u7684\u8fdb\u7a0b\u540d\u548c\u8fdb\u7a0b\u53f7\n\n# perf top --comms nginx,top         #\u4ec5\u663e\u793a\u5c5e\u4e8e\u6307\u5b9a\u8fdb\u7a0b\u7684\u7b26\u53f7\n\n# perf top --symbols kfree         #\u4ec5\u663e\u793a\u6307\u5b9a\u7684\u7b26\u53f7<\/code><\/pre>\n<p>\u4e3e\u4f8b3<\/p>\n<pre><code>#  perf stat ls \n\n Performance counter stats for &#039;ls&#039;:\n\n          0.653782 task-clock                #    0.691 CPUs utilized          \n                 0 context-switches          #    0.000 K\/sec                  \n                 0 CPU-migrations            #    0.000 K\/sec                  \n               247 page-faults               #    0.378 M\/sec                  \n         1,625,426 cycles                    #    2.486 GHz                    \n         1,050,293 stalled-cycles-frontend   #   64.62% frontend cycles idle   \n           838,781 stalled-cycles-backend    #   51.60% backend  cycles idle   \n         1,055,735 instructions              #    0.65  insns per cycle        \n                                             #    0.99  stalled cycles per insn\n           210,587 branches                  #  322.106 M\/sec                  \n            10,809 branch-misses             #    5.13% of all branches        \n\n       0.000945883 seconds time elapsed\n\n    \u8f93\u51fa\u5305\u62ecls\u7684\u6267\u884c\u65f6\u95f4\uff0c\u4ee5\u53ca10\u4e2a\u6027\u80fd\u4e8b\u4ef6\u7684\u7edf\u8ba1\u3002\n\n    task-clock\uff1a\u4efb\u52a1\u771f\u6b63\u5360\u7528\u7684\u5904\u7406\u5668\u65f6\u95f4\uff0c\u5355\u4f4d\u4e3ams\u3002CPUs utilized = task-clock \/ time elapsed\uff0cCPU\u7684\u5360\u7528\u7387\u3002\n\n    context-switches\uff1a\u4e0a\u4e0b\u6587\u7684\u5207\u6362\u6b21\u6570\u3002\n\n    CPU-migrations\uff1a\u5904\u7406\u5668\u8fc1\u79fb\u6b21\u6570\u3002Linux\u4e3a\u4e86\u7ef4\u6301\u591a\u4e2a\u5904\u7406\u5668\u7684\u8d1f\u8f7d\u5747\u8861\uff0c\u5728\u7279\u5b9a\u6761\u4ef6\u4e0b\u4f1a\u5c06\u67d0\u4e2a\u4efb\u52a1\u4ece\u4e00\u4e2aCPU\n\n    \u8fc1\u79fb\u5230\u53e6\u4e00\u4e2aCPU\u3002\n\n    page-faults\uff1a\u7f3a\u9875\u5f02\u5e38\u7684\u6b21\u6570\u3002\u5f53\u5e94\u7528\u7a0b\u5e8f\u8bf7\u6c42\u7684\u9875\u9762\u5c1a\u672a\u5efa\u7acb\u3001\u8bf7\u6c42\u7684\u9875\u9762\u4e0d\u5728\u5185\u5b58\u4e2d\uff0c\u6216\u8005\u8bf7\u6c42\u7684\u9875\u9762\u867d\u7136\u5728\u5185\n\n    \u5b58\u4e2d\uff0c\u4f46\u7269\u7406\u5730\u5740\u548c\u865a\u62df\u5730\u5740\u7684\u6620\u5c04\u5173\u7cfb\u5c1a\u672a\u5efa\u7acb\u65f6\uff0c\u90fd\u4f1a\u89e6\u53d1\u4e00\u6b21\u7f3a\u9875\u5f02\u5e38\u3002\u53e6\u5916TLB\u4e0d\u547d\u4e2d\uff0c\u9875\u9762\u8bbf\u95ee\u6743\u9650\u4e0d\u5339\u914d\n\n    \u7b49\u60c5\u51b5\u4e5f\u4f1a\u89e6\u53d1\u7f3a\u9875\u5f02\u5e38\u3002\n\n    cycles\uff1a\u6d88\u8017\u7684\u5904\u7406\u5668\u5468\u671f\u6570\u3002\u5982\u679c\u628a\u88abls\u4f7f\u7528\u7684cpu cycles\u770b\u6210\u662f\u4e00\u4e2a\u5904\u7406\u5668\u7684\uff0c\u90a3\u4e48\u5b83\u7684\u4e3b\u9891\u4e3a2.486GHz\u3002\n\n    \u53ef\u4ee5\u7528cycles \/ task-clock\u7b97\u51fa\u3002\n\n    stalled-cycles-frontend\uff1a\u7565\u8fc7\u3002\n\n    stalled-cycles-backend\uff1a\u7565\u8fc7\u3002\n\n    instructions\uff1a\u6267\u884c\u4e86\u591a\u5c11\u6761\u6307\u4ee4\u3002IPC\u4e3a\u5e73\u5747\u6bcf\u4e2acpu cycle\u6267\u884c\u4e86\u591a\u5c11\u6761\u6307\u4ee4\u3002\n\n    branches\uff1a\u9047\u5230\u7684\u5206\u652f\u6307\u4ee4\u6570\u3002branch-misses\u662f\u9884\u6d4b\u9519\u8bef\u7684\u5206\u652f\u6307\u4ee4\u6570\u3002\n\n#  perf stat -r 10 ls &gt; \/dev\/null         #\u6267\u884c10\u6b21\u7a0b\u5e8f\uff0c\u7ed9\u51fa\u6807\u51c6\u504f\u5dee\u4e0e\u671f\u671b\u7684\u6bd4\u503c\n\n#  perf stat -v ls &gt; \/dev\/null         #\u663e\u793a\u66f4\u8be6\u7ec6\u7684\u4fe1\u606f\n\n#  perf stat -n ls &gt; \/dev\/null         #\u53ea\u663e\u793a\u4efb\u52a1\u6267\u884c\u65f6\u95f4\uff0c\u4e0d\u663e\u793a\u6027\u80fd\u8ba1\u6570\u5668\n\n#  perf stat -a -A ls &gt; \/dev\/null         #\u5355\u72ec\u7ed9\u51fa\u6bcf\u4e2aCPU\u4e0a\u7684\u4fe1\u606f\n\n#  perf stat -e syscalls:sys_enter ls          #ls\u547d\u4ee4\u6267\u884c\u4e86\u591a\u5c11\u6b21\u7cfb\u7edf\u8c03\u7528<\/code><\/pre>\n<p>\u4e3e\u4f8b4<\/p>\n<pre><code>#  perf record -p `pgrep -d &#039;,&#039; nginx`      #\u8bb0\u5f55nginx\u8fdb\u7a0b\u7684\u6027\u80fd\u6570\u636e\n\n#  perf record ls -g    #\u8bb0\u5f55\u6267\u884cls\u65f6\u7684\u6027\u80fd\u6570\u636e\n\n# perf record -e syscalls:sys_enter ls      #\u8bb0\u5f55\u6267\u884cls\u65f6\u7684\u7cfb\u7edf\u8c03\u7528\uff0c\u53ef\u4ee5\u77e5\u9053\u54ea\u4e9b\u7cfb\u7edf\u8c03\u7528\u6700\u9891\u7e41<\/code><\/pre>\n<p>\u4e3e\u4f8b5<\/p>\n<pre><code>#   perf lock record ls      #\u8bb0\u5f55\n\n#   perf lock report      #\u62a5\u544a\n\n                Name   acquired  contended total wait (ns)   max wait (ns)   min wait (ns) \n\n &amp;mm-&gt;page_table_...        382          0               0               0               0 \n &amp;mm-&gt;page_table_...         72          0               0               0               0 \n           &amp;fs-&gt;lock         64          0               0               0               0 \n         dcache_lock         62          0               0               0               0 \n       vfsmount_lock         43          0               0               0               0 \n &amp;newf-&gt;file_lock...         41          0               0               0               0 \n\nName\uff1a\u5185\u6838\u9501\u7684\u540d\u5b57\u3002\naquired\uff1a\u8be5\u9501\u88ab\u76f4\u63a5\u83b7\u5f97\u7684\u6b21\u6570\uff0c\u56e0\u4e3a\u6ca1\u6709\u5176\u5b83\u5185\u6838\u8def\u5f84\u5360\u7528\u8be5\u9501\uff0c\u6b64\u65f6\u4e0d\u7528\u7b49\u5f85\u3002\ncontended\uff1a\u8be5\u9501\u7b49\u5f85\u540e\u83b7\u5f97\u7684\u6b21\u6570\uff0c\u6b64\u65f6\u88ab\u5176\u5b83\u5185\u6838\u8def\u5f84\u5360\u7528\uff0c\u9700\u8981\u7b49\u5f85\u3002\ntotal wait\uff1a\u4e3a\u4e86\u83b7\u5f97\u8be5\u9501\uff0c\u603b\u5171\u7684\u7b49\u5f85\u65f6\u95f4\u3002\nmax wait\uff1a\u4e3a\u4e86\u83b7\u5f97\u8be5\u9501\uff0c\u6700\u5927\u7684\u7b49\u5f85\u65f6\u95f4\u3002\nmin wait\uff1a\u4e3a\u4e86\u83b7\u5f97\u8be5\u9501\uff0c\u6700\u5c0f\u7684\u7b49\u5f85\u65f6\u95f4\u3002<\/code><\/pre>\n<p>\u4e3e\u4f8b6<\/p>\n<pre><code>#  perf kmem record ls      #\u8bb0\u5f55\n\n#  perf kmem stat --caller --alloc -l 20      #\u62a5\u544a\n\n------------------------------------------------------------------------------------------------------\n Callsite                           | Total_alloc\/Per | Total_req\/Per   | Hit      | Ping-pong | Frag\n------------------------------------------------------------------------------------------------------\n perf_event_mmap+ec                 |    311296\/8192  |    155952\/4104  |       38 |        0 | 49.902%\n proc_reg_open+41                   |        64\/64    |        40\/40    |        1 |        0 | 37.500%\n __kmalloc_node+4d                  |      1024\/1024  |       664\/664   |        1 |        0 | 35.156%\n ext3_readdir+5bd                   |        64\/64    |        48\/48    |        1 |        0 | 25.000%\n load_elf_binary+8ec                |       512\/512   |       392\/392   |        1 |        0 | 23.438%\n\nCallsite\uff1a\u5185\u6838\u4ee3\u7801\u4e2d\u8c03\u7528kmalloc\u548ckfree\u7684\u5730\u65b9\u3002\nTotal_alloc\/Per\uff1a\u603b\u5171\u5206\u914d\u7684\u5185\u5b58\u5927\u5c0f\uff0c\u5e73\u5747\u6bcf\u6b21\u5206\u914d\u7684\u5185\u5b58\u5927\u5c0f\u3002\nTotal_req\/Per\uff1a\u603b\u5171\u8bf7\u6c42\u7684\u5185\u5b58\u5927\u5c0f\uff0c\u5e73\u5747\u6bcf\u6b21\u8bf7\u6c42\u7684\u5185\u5b58\u5927\u5c0f\u3002\nHit\uff1a\u8c03\u7528\u7684\u6b21\u6570\u3002\nPing-pong\uff1akmalloc\u548ckfree\u4e0d\u88ab\u540c\u4e00\u4e2aCPU\u6267\u884c\u65f6\u7684\u6b21\u6570\uff0c\u8fd9\u4f1a\u5bfc\u81f4cache\u6548\u7387\u964d\u4f4e\u3002\nFrag\uff1a\u788e\u7247\u6240\u5360\u7684\u767e\u5206\u6bd4\uff0c\u788e\u7247 = \u5206\u914d\u7684\u5185\u5b58 - \u8bf7\u6c42\u7684\u5185\u5b58\uff0c\u8fd9\u90e8\u5206\u662f\u6d6a\u8d39\u7684\u3002\n\u6709\u4f7f\u7528--alloc\u9009\u9879\uff0c\u8fd8\u4f1a\u770b\u5230Alloc Ptr\uff0c\u5373\u6240\u5206\u914d\u5185\u5b58\u7684\u5730\u5740\u3002<\/code><\/pre>\n<p>\u4e3e\u4f8b7<\/p>\n<pre><code>#  perf sched record sleep 10    \n\n#  perf report latency --sort max    \n\n ---------------------------------------------------------------------------------------------------------------\n  Task                  |   Runtime ms  | Switches | Average delay ms | Maximum delay ms | Maximum delay at     |\n ---------------------------------------------------------------------------------------------------------------\n  events\/10:61          |      0.655 ms |       10 | avg:    0.045 ms | max:    0.161 ms | max at: 9804.958730 s\n  sleep:11156           |      2.263 ms |        4 | avg:    0.052 ms | max:    0.118 ms | max at: 9804.865552 s\n  edac-poller:1125      |      0.598 ms |       10 | avg:    0.042 ms | max:    0.113 ms | max at: 9804.958698 s\n  events\/2:53           |      0.676 ms |       10 | avg:    0.037 ms | max:    0.102 ms | max at: 9814.751605 s\n  perf:11155            |      2.109 ms |        1 | avg:    0.068 ms | max:    0.068 ms | max at: 9814.867918 s\n\nTASK\uff1a\u8fdb\u7a0b\u540d\u548cpid\u3002\nRuntime\uff1a\u5b9e\u9645\u7684\u8fd0\u884c\u65f6\u95f4\u3002\nSwitches\uff1a\u8fdb\u7a0b\u5207\u6362\u7684\u6b21\u6570\u3002\nAverage delay\uff1a\u5e73\u5747\u7684\u8c03\u5ea6\u5ef6\u8fdf\u3002\nMaximum delay\uff1a\u6700\u5927\u7684\u8c03\u5ea6\u5ef6\u8fdf\u3002\nMaximum delay at\uff1a\u6700\u5927\u8c03\u5ea6\u5ef6\u8fdf\u53d1\u751f\u7684\u65f6\u523b\u3002<\/code><\/pre>\n<p>\u4e3e\u4f8b8<\/p>\n<pre><code>#  perf probe --line schedule    #\u524d\u9762\u6709\u884c\u53f7\u7684\u53ef\u4ee5\u63a2\u6d4b\uff0c\u6ca1\u6709\u884c\u53f7\u7684\u5c31\u4e0d\u884c\u4e86\n\n#  perf report latency --sort max    #\u5728schedule\u51fd\u6570\u768412\u5904\u589e\u52a0\u4e00\u4e2a\u63a2\u6d4b\u70b9<\/code><\/pre>\n<h2>3.3 perf\u5de5\u5177\u539f\u7406\u8be6\u89e3<\/h2>\n<p>Linux\u6027\u80fd\u8ba1\u6570\u5668\u662f\u4e00\u4e2a\u65b0\u7684\u57fa\u4e8e\u5185\u6838\u7684\u5b50\u7cfb\u7edf\uff0c\u5b83\u63d0\u4f9b\u4e00\u4e2a\u6027\u80fd\u5206\u6790\u6846\u67b6\uff0c\u6bd4\u5982\u786c\u4ef6\uff08CPU\u3001PMU(Performance Monitoring Unit)\uff09\u529f\u80fd\u548c\u8f6f\u4ef6(\u8f6f\u4ef6\u8ba1\u6570\u5668\u3001tracepoint)\u529f\u80fd\u3002<br \/>\n\u901a\u8fc7perf\uff0c\u5e94\u7528\u7a0b\u5e8f\u53ef\u4ee5\u5229\u7528PMU\u3001tracepoint\u548c\u5185\u6838\u4e2d\u7684\u8ba1\u6570\u5668\u6765\u8fdb\u884c\u6027\u80fd\u7edf\u8ba1\u3002\u5b83\u4e0d\u4f46\u53ef\u4ee5\u5206\u6790\u6307\u5b9a\u5e94\u7528\u7a0b\u5e8f\u7684\u6027\u80fd\u95ee\u9898\uff08per thread\uff09\uff0c\u4e5f\u53ef\u4ee5\u7528\u6765\u5206\u6790\u5185\u6838\u7684\u6027\u80fd\u95ee\u9898\uff0c\u5f53\u7136\u4e5f\u53ef\u4ee5\u540c\u65f6\u5206\u6790\u5e94\u7528\u7a0b\u5e8f\u548c\u5185\u6838\uff0c\u4ece\u800c\u5168\u9762\u7406\u89e3\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684\u6027\u80fd\u74f6\u9888\u3002<\/p>\n<p>\u4f7f\u7528perf\uff0c\u53ef\u4ee5\u5206\u6790\u7a0b\u5e8f\u8fd0\u884c\u671f\u95f4\u53d1\u751f\u7684\u786c\u4ef6\u4e8b\u4ef6\uff0c\u6bd4\u5982instructions retired\u3001processor clock cycles\u7b49\uff1b\u4e5f\u53ef\u4ee5\u5206\u6790\u8f6f\u4ef6\u4e8b\u4ef6\uff0c\u6bd4\u5982page fault\u548c\u8fdb\u7a0b\u5207\u6362\u3002<\/p>\n<h3>(1) \u4ec0\u4e48\u662fPMU<\/h3>\n<p>Performance Monitor Unit\uff0c\u6027\u80fd\u76d1\u89c6\u5355\u5143\uff0c\u5176\u5b9eCPU\u63d0\u4f9b\u7684\u4e00\u4e2a\u5355\u5143\uff0c\u5c5e\u4e8e\u786c\u4ef6\u7684\u8303\u7574\u3002\u901a\u8fc7\u8bbf\u95ee\u76f8\u5173\u7684\u5bc4\u5b58\u5668\u80fd\u8bfb\u53d6\u5230CPU\u7684\u4e00\u4e9b\u6027\u80fd\u6570\u636e\uff0c\u76ee\u524d\u5927\u90e8\u5206CPU\u90fd\u4f1a\u63d0\u4f9b\u76f8\u5e94\u7684PMU\u3002<\/p>\n<h3>(2) \u786c\u4ef6\u7279\u6027\u4e4bcache<\/h3>\n<p>\u5185\u5b58\u8bfb\u5199\u662f\u5f88\u5feb\u7684\uff0c\u4f46\u662f\u8fd8\u662f\u65e0\u6cd5\u548c\u5904\u7406\u5668\u6307\u4ee4\u6267\u884c\u901f\u5ea6\u76f8\u6bd4\u3002\u4e3a\u4e86\u4ece\u5185\u5b58\u4e2d\u8bfb\u53d6\u6307\u4ee4\u548c\u6570\u636e\uff0c\u5904\u7406\u5668\u9700\u8981\u7b49\u5f85\uff0c\u7528\u5904\u7406\u5668\u65f6\u95f4\u6765\u8861\u91cf\uff0c\u8fd9\u79cd\u7b49\u5f85\u975e\u5e38\u6f2b\u957f\u3002cache\u662f\u4e00\u79cdSRAM\uff0c\u8bfb\u5199\u901f\u5ea6\u975e\u5e38\u5feb\uff0c\u80fd\u548c\u5904\u7406\u5668\u76f8\u5339\u914d\u3002\u56e0\u6b64\u5c06\u5e38\u7528\u7684\u6570\u636e\u4fdd\u5b58\u5728cache\u4e2d\uff0c\u5904\u7406\u5668\u4fbf\u65e0\u9700\u7b49\u5f85\uff0c\u4ece\u800c\u63d0\u9ad8\u6027\u80fd\u3002cache\u7684\u5c3a\u5bf8\u4e00\u822c\u90fd\u5f88\u5c0f\uff0c\u5145\u5206\u5229\u7528cache\u662f\u8f6f\u4ef6\u8c03\u4f18\u975e\u5e38\u91cd\u8981\u90e8\u5206\u3002<\/p>\n<h3>(3) tracepoints<\/h3>\n<p>tracepoints\u662f\u6563\u843d\u5728\u5185\u6838\u6e90\u7801\u4e2d\u7684\u4e00\u4e9bhook\uff0c\u5b83\u4eec\u53ef\u4ee5\u5728\u7279\u5b9a\u7684\u4ee3\u7801\u88ab\u6267\u884c\u5230\u65f6\u89e6\u53d1\uff0c\u8fd9\u4e00\u7279\u6027\u53ef\u4ee5\u88ab\u5404\u79cdtrace\/debug\u5de5\u5177\u6240\u4f7f\u7528\u3002<\/p>\n<p>perf\u5c06tracepoint\u4ea7\u751f\u7684\u65f6\u95f4\u8bb0\u5f55\u4e0b\u6765\uff0c\u751f\u6210\u62a5\u544a\uff0c\u901a\u8fc7\u5206\u6790\u8fd9\u4e9b\u62a5\u544a\uff0c\u8c03\u4f18\u4eba\u5458\u4fbf\u53ef\u4ee5\u4e86\u89e3\u7a0b\u5e8f\u8fd0\u884c\u671f\u95f4\u5185\u6838\u7684\u5404\u79cd\u7ec6\u8282\uff0c\u5bf9\u6027\u80fd\u75c7\u72b6\u505a\u51fa\u51c6\u786e\u7684\u8bca\u65ad\u3002<\/p>\n<p>\u8fd9\u4e9btracepint\u7684\u5bf9\u5e94\u7684sysfs\u8282\u70b9\u5728\/sys\/kernel\/debug\/tracing\/events\u76ee\u5f55\u4e0b\u3002<\/p>\n<p>\u4e0b\u56fe\u5c55\u793aperf\u6574\u4f53\u67b6\u6784<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/1-2.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/1-2.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h3>(4) perf \u4f7f\u7528<\/h3>\n<p>perf\u63d0\u4f9b\u7684\u4e8b\u4ef6\u4e3b\u8981\u53ef\u4ee5\u5206\u4e3a\u4e09\u79cd\uff1a<\/p>\n<ul>\n<li>Hardware Event\u7531PMU\u90e8\u4ef6\u4ea7\u751f\uff0c\u5728\u7279\u5b9a\u7684\u6761\u4ef6\u4e0b\u63a2\u6d4b\u6027\u80fd\u4e8b\u4ef6\u662f\u5426\u53d1\u751f\u4ee5\u53ca\u53d1\u751f\u7684\u6b21\u6570\u3002\u6bd4\u5982cache\u547d\u4e2d\u3002<\/li>\n<li>Software Event\u662f\u5185\u6838\u4ea7\u751f\u7684\u4e8b\u4ef6\uff0c\u5206\u5e03\u5728\u5404\u4e2a\u529f\u80fd\u6a21\u5757\u4e2d\uff0c\u7edf\u8ba1\u548c\u64cd\u4f5c\u7cfb\u7edf\u76f8\u5173\u6027\u80fd\u4e8b\u4ef6\u3002\u6bd4\u5982\u8fdb\u7a0b\u5207\u6362\uff0ctick\u6570\u7b49\u3002<\/li>\n<li>Tracepoint Event\u662f\u5185\u6838\u4e2d\u9759\u6001tracepoint\u6240\u89e6\u53d1\u7684\u4e8b\u4ef6\uff0c\u8fd9\u4e9btracepoint\u7528\u6765\u5224\u65ad\u7a0b\u5e8f\u8fd0\u884c\u671f\u95f4\u5185\u6838\u7684\u884c\u4e3a\u7ec6\u8282\uff0c\u6bd4\u5982slab\u5206\u914d\u5668\u7684\u5206\u914d\u6b21\u6570\u7b49\u3002<\/li>\n<\/ul>\n<p>perf &#8211;help\u4e4b\u540e\u53ef\u4ee5\u770b\u5230perf\u7684\u4e8c\u7ea7\u547d\u4ee4\uff08\u5e38\u7528\u7684\u4ee5\u9ed1\u4f53\u6807\u51fa\uff09<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/2-2.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/2-2.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h1>\u56db \u706b\u7130\u56fe\u5236\u4f5c\u4e0e\u89e3\u8bfb<\/h1>\n<h2>4.1 \u628aperf\u7ed3\u679c\u5236\u4f5c\u6210\u706b\u7130\u56fe<\/h2>\n<p>\u6211\u4eec\u53ef\u4ee5\u628aperf\u6355\u6349\u7684\u4fe1\u606f\u5236\u4f5c\u6210\u706b\u7130\u56fe\u6765\u65b9\u4fbf\u67e5\u770b\u4e0e\u5206\u6790CPU \u7684\u8c03\u7528\u6808<\/p>\n<p>\u706b\u7130\u56fe\uff08Flame Graph\uff09\u662f\u7531 Linux \u6027\u80fd\u4f18\u5316\u5927\u5e08 Brendan Gregg \u53d1\u660e\u7684\uff0c\u548c\u6240\u6709\u5176\u4ed6\u7684 profiling \u65b9\u6cd5\u4e0d\u540c\u7684\u662f\uff0c\u706b\u7130\u56fe\u4ee5\u4e00\u4e2a\u5168\u5c40\u7684\u89c6\u91ce\u6765\u770b\u5f85\u65f6\u95f4\u5206\u5e03\uff0c\u5b83\u4ece\u5e95\u90e8\u5f80\u9876\u90e8\uff0c\u5217\u51fa\u6240\u6709\u53ef\u80fd\u5bfc\u81f4\u6027\u80fd\u74f6\u9888\u7684\u8c03\u7528\u6808\u3002<\/p>\n<p>\u4e0b\u8f7dFlameGraph\u5de5\u5177\uff0c<\/p>\n<pre><code>git clone https:\/\/github.com\/brendangregg\/FlameGraph.git<\/code><\/pre>\n<p>\u751f\u6210\u706b\u7130\u56fe\uff0c\u4e00\u822c\u9075\u5faa\u4e00\u4e0b\u6d41\u7a0b\uff1a<\/p><div id=\"rml_readmorelogin_placeholder\" style=\"position:relative;\"><div id=\"rml_fade_content\" style=\"position: absolute;\r\ntop:-10em;\r\nwidth:100%;\r\nheight:10em;\r\nbackground: -webkit-linear-gradient(rgba(255, 255, 255, 0) 0%,#ffffff 100%);\r\nbackground-image: -moz-linear-gradient(rgba(255, 255, 255, 0) 0%,#ffffff 100%);\r\nbackground-image: -o-linear-gradient(rgba(255, 255, 255, 0) 0%,#ffffff 100%);\r\nbackground-image: linear-gradient(rgba(255, 255, 255, 0) 0%,#ffffff 100%);\r\nbackground-image: -ms-linear-gradient(rgba(255, 255, 255, 0) 0%,#ffffff 100%);\"><\/div><div class=\"wpf-controller aru_rml_from_in_post\" style=\"background-color:#eeeeee;border:5px solid #cce6ff;\" id=\"ARU_ReadMoreLogin_ReadMoreLoginController\"><h2 id=\"Header\">\u67e5\u770b\u66f4\u591a<\/h2><div id=\"Message\"><p>\u8054\u7cfb\u7ba1\u7406\u5458\u5fae\u4fe1tutu19192010\uff0c\u6ce8\u518c\u8d26\u53f7<\/p>\n<\/div><div id=\"StatusBarHeader\"><\/div><form id=\"ARU_ReadMoreLogin_ReadMoreLoginController\"><input name=\"post_id\" value=\"7408\" type=\"hidden\"\/><input name=\"_init_callback\" value=\"InitLogin\" type=\"hidden\"\/><input name=\"post_id\" value=\"7408\" type=\"hidden\"\/><input name=\"rt_ype\" value=\"1\" type=\"hidden\"\/><input name=\"nonce\" value=\"6976a72a2c\" type=\"hidden\"\/><input name=\"_wpnonce\" value=\"b0e6d8f8bf\" type=\"hidden\"\/><input name=\"_controller\" value=\"ARU_ReadMoreLogin\\ReadMoreLoginController\" type=\"hidden\"\/><input name=\"_proxy_controller\" value=\"ARU_ReadMoreLogin\\ReadMoreLoginController\" type=\"hidden\"\/><input name=\"_view\" value=\"ARU_ReadMoreLogin\\ReadMoreLoginView\" type=\"hidden\"\/><table class=\"wpf-table-placeholder\"><tbody class=\"wpf-table-placeholder\"><tr class=\"wpf-table-placeholder\"><td class=\"wpf-table-placeholder-input\" width=\"400px\"><table class=\"wpf-table-placeholder\"><tbody class=\"wpf-table-placeholder\"><tr class=\"wpf-table-placeholder\"><th class=\"wpf-table-placeholder-input\"><label class=\"wpf-label\">Username:<\/label><\/th><\/tr><tr class=\"wpf-table-placeholder\"><td class=\"wpf-table-placeholder-input\"><input class=\"regular-text text_input\" name=\"username\" value=\"\" type=\"text\"\/><\/td><\/tr><tr class=\"wpf-table-placeholder\"><th class=\"wpf-table-placeholder-input\"><label class=\"wpf-label\">Password:<\/label><\/th><\/tr><tr class=\"wpf-table-placeholder\"><td class=\"wpf-table-placeholder-input\"><input class=\"regular-text text_input\" name=\"password\" value=\"\" type=\"password\"\/><\/td><\/tr><\/tbody><\/table><p class=\"wpf-table-placeholder submit\"><button class=\"wp_plugin_framework_ajax_button\" type=\"button\" style=\"background-color:#4D90FE;;color:#ffffff;;border:1px solid #3079ed;\" name=\"_event\" value=\"ButtonLogin\">Log in<\/button><\/p><\/td><td class=\"wpf-table-placeholder-input\"><\/td><\/tr><\/tbody><\/table><\/form><div id=\"ButtonStartRegister\"><a href=\"https:\/\/egonlin.com\/wp-login.php?action=register\">Register<\/a><\/div><div id=\"Link1\"><a href=\"https:\/\/egonlin.com\/wp-login.php?action=lostpassword\">Forgotten username or password?<\/a><\/div><div id=\"StatusBarFooter\"><\/div><\/div><\/div><div id=aru_remaining_content><\/div>","protected":false},"excerpt":{"rendered":"<p>\u4e00 \u5bb9\u5668\u5171\u4eab\u5bbf\u4e3b\u673a\u5185\u6838\u5e26\u6765\u7684\u5f71\u54cd \u5bb9\u5668\u91cc\u7684\u8fdb\u7a0b\u5f52\u6839\u7ed3\u5e95\u90fd\u662f\u8fd0\u884c\u5728\u5bbf\u4e3b\u673a\u4e0a\u7684\u8fdb\u7a0b\uff0c\u6240\u4ee5\u5bbf\u4e3b\u673a\u4e00\u65e6\u51fa\u73b0\u6027\u80fd\u95ee\u9898\uff0c\u5b83 [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[426,422],"tags":[],"_links":{"self":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/7408"}],"collection":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=7408"}],"version-history":[{"count":0,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/7408\/revisions"}],"wp:attachment":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=7408"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=7408"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=7408"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}