You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
arthas/en/trace.html

415 lines
23 KiB
HTML

This file contains ambiguous Unicode characters!

This file contains ambiguous Unicode characters that may be confused with others in your current locale. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to highlight these characters.

<!DOCTYPE html>
<!--[if IE 8]><html class="no-js lt-ie9" lang="en" > <![endif]-->
<!--[if gt IE 8]><!--> <html class="no-js" lang="en" > <!--<![endif]-->
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>trace &mdash; Arthas 3.0.6-SNAPSHOT documentation</title>
<link rel="shortcut icon" href="_static/favicon.ico"/>
<link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
<link rel="stylesheet" href="_static/pygments.css" type="text/css" />
<link rel="stylesheet" href="_static/overrides.css" type="text/css" />
<link rel="index" title="Index" href="genindex.html" />
<link rel="search" title="Search" href="search.html" />
<link rel="next" title="stack" href="stack.html" />
<link rel="prev" title="Fundamental Fields in Expressions" href="advice-class.html" />
<script src="_static/center_page.js"></script>
<script src="_static/js/modernizr.min.js"></script>
</head>
<body class="wy-body-for-nav">
<div class="wy-grid-for-nav">
<nav data-toggle="wy-nav-shift" class="wy-nav-side">
<div class="wy-side-scroll">
<div class="wy-side-nav-search">
<a href="index.html" class="icon icon-home"> Arthas
</a>
<div class="version">
3.0.6-SNAPSHOT
</div>
<div role="search">
<form id="rtd-search-form" class="wy-form" action="search.html" method="get">
<input type="text" name="q" placeholder="Search docs" />
<input type="hidden" name="check_keywords" value="yes" />
<input type="hidden" name="area" value="default" />
</form>
</div>
</div>
<div class="wy-menu wy-menu-vertical" data-spy="affix" role="navigation" aria-label="main navigation">
<ul class="current">
<li class="toctree-l1"><a class="reference internal" href="install-detail.html">Installation</a></li>
<li class="toctree-l1"><a class="reference internal" href="quick-start.html">Quick start</a></li>
<li class="toctree-l1"><a class="reference internal" href="advanced-use.html">Advanced usage</a></li>
<li class="toctree-l1 current"><a class="reference internal" href="commands.html">Commands</a><ul class="current">
<li class="toctree-l2"><a class="reference internal" href="dashboard.html">dashboard</a></li>
<li class="toctree-l2"><a class="reference internal" href="thread.html">thread</a></li>
<li class="toctree-l2"><a class="reference internal" href="jvm.html">jvm</a></li>
<li class="toctree-l2"><a class="reference internal" href="sysprop.html">sysprop</a></li>
<li class="toctree-l2"><a class="reference internal" href="sysenv.html">sysenv</a></li>
<li class="toctree-l2"><a class="reference internal" href="getstatic.html">getstatic</a></li>
<li class="toctree-l2"><a class="reference internal" href="ognl.html">ognl</a></li>
<li class="toctree-l2"><a class="reference internal" href="sc.html">sc</a></li>
<li class="toctree-l2"><a class="reference internal" href="sm.html">sm</a></li>
<li class="toctree-l2"><a class="reference internal" href="dump.html">dump</a></li>
<li class="toctree-l2"><a class="reference internal" href="jad.html">jad</a></li>
<li class="toctree-l2"><a class="reference internal" href="classloader.html">classloader</a></li>
<li class="toctree-l2"><a class="reference internal" href="redefine.html">redefine</a></li>
<li class="toctree-l2"><a class="reference internal" href="monitor.html">monitor</a></li>
<li class="toctree-l2"><a class="reference internal" href="watch.html">watch</a></li>
<li class="toctree-l2 current"><a class="current reference internal" href="#">trace</a><ul>
<li class="toctree-l3"><a class="reference internal" href="#parameters">Parameters</a></li>
<li class="toctree-l3"><a class="reference internal" href="#notice">Notice</a></li>
<li class="toctree-l3"><a class="reference internal" href="#usage">Usage</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="stack.html">stack</a></li>
<li class="toctree-l2"><a class="reference internal" href="tt.html">tt</a></li>
<li class="toctree-l2"><a class="reference internal" href="options.html">options</a></li>
<li class="toctree-l2"><a class="reference internal" href="commands.html#basic-arthas-commands">Basic Arthas Commands</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference external" href="https://github.com/alibaba/arthas/issues?q=label%3Auser-case">User cases</a></li>
<li class="toctree-l1"><a class="reference external" href="https://github.com/alibaba/arthas/issues?q=label%3Aquestion-answered">Questions and answers</a></li>
<li class="toctree-l1"><a class="reference external" href="https://github.com/alibaba/arthas">Fork me at GitHub</a></li>
<li class="toctree-l1"><a class="reference external" href="https://github.com/alibaba/arthas/blob/master/CONTRIBUTING.md">CONTRIBUTING</a></li>
<li class="toctree-l1"><a class="reference internal" href="release-notes.html">Release Notes</a></li>
</ul>
</div>
</div>
</nav>
<section data-toggle="wy-nav-shift" class="wy-nav-content-wrap">
<nav class="wy-nav-top" aria-label="top navigation">
<i data-toggle="wy-nav-top" class="fa fa-bars"></i>
<a href="index.html">Arthas</a>
</nav>
<div class="wy-nav-content">
<div class="rst-content">
<div role="navigation" aria-label="breadcrumbs navigation">
<ul class="wy-breadcrumbs">
<li><a href="index.html">Docs</a> &raquo;</li>
<li><a href="commands.html">All Commands</a> &raquo;</li>
<li>trace</li>
<li class="wy-breadcrumbs-aside">
<a href="https://github.com/alibaba/arthas/blob/master/site/src/site/sphinx/en/trace.md" class="fa fa-github"> Edit on GitHub</a>
</li>
</ul>
<hr/>
</div>
<div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article">
<div itemprop="articleBody">
<div class="section" id="trace">
<span id="trace"></span><h1>trace<a class="headerlink" href="#trace" title="Permalink to this headline"></a></h1>
<blockquote>
<div>Trace method calling path, and output the time cost for each node in the path.</div></blockquote>
<p><code class="docutils literal notranslate"><span class="pre">trace</span></code> can track the calling path specified by <code class="docutils literal notranslate"><span class="pre">class-pattern</span></code> / <code class="docutils literal notranslate"><span class="pre">method-pattern</span></code>, and calculate the time cost on the whole path.</p>
<div class="section" id="parameters">
<span id="parameters"></span><h2>Parameters<a class="headerlink" href="#parameters" title="Permalink to this headline"></a></h2>
<table border="1" class="docutils">
<thead>
<tr>
<th align="right">Name</th>
<th align="left">Specification</th>
</tr>
</thead>
<tbody>
<tr>
<td align="right"><em>class-pattern</em></td>
<td align="left">pattern for the class name</td>
</tr>
<tr>
<td align="right"><em>method-pattern</em></td>
<td align="left">pattern for the method name</td>
</tr>
<tr>
<td align="right"><em>condition-express</em></td>
<td align="left">condition expression</td>
</tr>
<tr>
<td align="right"><code>[E]</code></td>
<td align="left">enable regex match, the default behavior is wildcards match</td>
</tr>
<tr>
<td align="right"><code>[n:]</code></td>
<td align="left">execution times</td>
</tr>
<tr>
<td align="right">#cost</td>
<td align="left">time cost</td>
</tr>
</tbody>
</table><p>Theres one thing worthy noting here is observation expression. The observation expression supports OGNL grammar, for example, you can come up a expression like this <code class="docutils literal notranslate"><span class="pre">&quot;{params,returnObj}&quot;</span></code>. All OGNL expressions are supported as long as they are legal to the grammar.</p>
<p>Thanks for <code class="docutils literal notranslate"><span class="pre">advice</span></code>s data structure, it is possible to observe from varieties of different angles. Inside <code class="docutils literal notranslate"><span class="pre">advice</span></code> parameter, all necessary information for notification can be found.</p>
<p>Pls. refer to <a class="reference internal" href="advice-class.html"><span class="doc">core parameters in expression</span></a> for more details.</p>
<ul class="simple">
<li>Pls. also refer to <a class="reference external" href="https://github.com/alibaba/arthas/issues/71">https://github.com/alibaba/arthas/issues/71</a> for more advanced usage</li>
<li>OGNL official site: <a class="reference external" href="https://commons.apache.org/proper/commons-ognl/language-guide.html">https://commons.apache.org/proper/commons-ognl/language-guide.html</a></li>
</ul>
<p>Many times what we are interested is the exact trace result when the method call takes time over one particular period. It is possible to achieve this in Arthas, for example: <code class="docutils literal notranslate"><span class="pre">trace</span> <span class="pre">*StringUtils</span> <span class="pre">isBlank</span> <span class="pre">'$cost&gt;100'</span></code> means trace result will only be output when the executing time exceeds 100ms.</p>
<blockquote>
<div><p>Notes:</p>
<ol class="simple">
<li><code class="docutils literal notranslate"><span class="pre">watch</span></code>/<code class="docutils literal notranslate"><span class="pre">stack</span></code>/<code class="docutils literal notranslate"><span class="pre">trace</span></code>, these three commands all support <code class="docutils literal notranslate"><span class="pre">$cost</span></code>.</li>
<li>On version <code class="docutils literal notranslate"><span class="pre">3.0</span></code>, pls. use <code class="docutils literal notranslate"><span class="pre">#cost</span></code> instead of <code class="docutils literal notranslate"><span class="pre">$cost</span></code>.</li>
</ol>
</div></blockquote>
</div>
<div class="section" id="notice">
<span id="notice"></span><h2>Notice<a class="headerlink" href="#notice" title="Permalink to this headline"></a></h2>
<p><code class="docutils literal notranslate"><span class="pre">trace</span></code> is handy to help discovering and locating the performance flaws in your system, but pls. note Arthas can only trace the first level method call each time.</p>
</div>
<div class="section" id="usage">
<span id="usage"></span><h2>Usage<a class="headerlink" href="#usage" title="Permalink to this headline"></a></h2>
<p>Sample code:</p>
<div class="highlight-java notranslate"><div class="highlight"><pre><span></span> <span class="kd">public</span> <span class="kd">static</span> <span class="kt">void</span> <span class="nf">main</span><span class="o">(</span><span class="n">String</span><span class="o">[]</span> <span class="n">args</span><span class="o">)</span> <span class="o">{</span>
<span class="n">List</span><span class="o">&lt;</span><span class="n">String</span><span class="o">&gt;</span> <span class="n">list</span> <span class="o">=</span> <span class="k">new</span> <span class="n">ArrayList</span><span class="o">&lt;</span><span class="n">String</span><span class="o">&gt;();</span>
<span class="n">list</span><span class="o">.</span><span class="na">add</span><span class="o">(</span><span class="s">&quot;a&quot;</span><span class="o">);</span>
<span class="n">list</span><span class="o">.</span><span class="na">add</span><span class="o">(</span><span class="s">&quot;b&quot;</span><span class="o">);</span>
<span class="n">List</span><span class="o">&lt;</span><span class="n">String</span><span class="o">&gt;</span> <span class="n">list2</span> <span class="o">=</span> <span class="k">new</span> <span class="n">ArrayList</span><span class="o">&lt;</span><span class="n">String</span><span class="o">&gt;();</span>
<span class="n">list2</span><span class="o">.</span><span class="na">add</span><span class="o">(</span><span class="s">&quot;c&quot;</span><span class="o">);</span>
<span class="n">list2</span><span class="o">.</span><span class="na">add</span><span class="o">(</span><span class="s">&quot;d&quot;</span><span class="o">);</span>
<span class="kt">int</span> <span class="n">len</span> <span class="o">=</span> <span class="n">add</span><span class="o">(</span><span class="n">list</span><span class="o">,</span> <span class="n">list2</span><span class="o">);</span>
<span class="o">}</span>
<span class="kd">private</span> <span class="kd">static</span> <span class="kt">int</span> <span class="nf">add</span><span class="o">(</span><span class="n">List</span><span class="o">&lt;</span><span class="n">String</span><span class="o">&gt;</span> <span class="n">list</span><span class="o">,</span> <span class="n">List</span><span class="o">&lt;</span><span class="n">String</span><span class="o">&gt;</span> <span class="n">list2</span><span class="o">)</span> <span class="o">{</span>
<span class="kt">int</span> <span class="n">i</span> <span class="o">=</span> <span class="mi">10</span><span class="o">;</span>
<span class="k">while</span> <span class="o">(</span><span class="n">i</span> <span class="o">&gt;=</span> <span class="mi">0</span><span class="o">)</span> <span class="o">{</span>
<span class="k">try</span> <span class="o">{</span>
<span class="n">hehe</span><span class="o">(</span><span class="n">i</span><span class="o">);</span>
<span class="o">}</span> <span class="k">catch</span> <span class="o">(</span><span class="n">Throwable</span> <span class="n">t</span><span class="o">)</span> <span class="o">{</span>
<span class="n">t</span><span class="o">.</span><span class="na">printStackTrace</span><span class="o">();</span>
<span class="o">}</span>
<span class="n">i</span><span class="o">--;</span>
<span class="o">}</span>
<span class="n">list</span><span class="o">.</span><span class="na">addAll</span><span class="o">(</span><span class="n">list2</span><span class="o">);</span>
<span class="k">return</span> <span class="n">list</span><span class="o">.</span><span class="na">size</span><span class="o">();</span>
<span class="o">}</span>
<span class="kd">private</span> <span class="kd">static</span> <span class="kt">void</span> <span class="nf">hehe</span><span class="o">(</span><span class="kt">int</span> <span class="n">i</span><span class="o">)</span> <span class="o">{</span>
<span class="k">if</span> <span class="o">(</span><span class="n">i</span> <span class="o">==</span> <span class="mi">0</span><span class="o">)</span> <span class="o">{</span>
<span class="k">throw</span> <span class="k">new</span> <span class="n">RuntimeException</span><span class="o">(</span><span class="s">&quot;ZERO&quot;</span><span class="o">);</span>
<span class="o">}</span>
<span class="o">}</span>
</pre></div>
</div>
<p>Trace down method <code class="docutils literal notranslate"><span class="pre">add</span></code>:</p>
<div class="highlight-shell notranslate"><div class="highlight"><pre><span></span>$ trace com.alibaba.sample.petstore.web.store.module.screen.ItemList add params.length<span class="o">==</span><span class="m">2</span>
Press Ctrl+C to abort.
Affect<span class="o">(</span>class-cnt:1 , method-cnt:1<span class="o">)</span> cost in <span class="m">144</span> ms.
<span class="sb">`</span>---Tracing...
<span class="sb">`</span>---<span class="o">[</span>2ms<span class="o">]</span>com.alibaba.sample.petstore.web.store.module.screen.ItemList:add<span class="o">()</span>
+---<span class="o">[</span><span class="m">0</span>,0,0ms,11<span class="o">]</span>com.alibaba.sample.petstore.web.store.module.screen.ItemList:hehe<span class="o">()</span> <span class="o">[</span>throws Exception<span class="o">]</span>
+---<span class="o">[</span>1ms<span class="o">]</span>java.lang.Throwable:printStackTrace<span class="o">()</span>
+---<span class="o">[</span>0ms<span class="o">]</span>java.util.List:addAll<span class="o">()</span>
<span class="sb">`</span>---<span class="o">[</span>0ms<span class="o">]</span>java.util.List:size<span class="o">()</span>
</pre></div>
</div>
<p>Filter by time cost:</p>
<div class="highlight-shell notranslate"><div class="highlight"><pre><span></span>$ trace com.alibaba.sample.petstore.web.store.module.screen.ItemList execute <span class="c1">#cost&gt;4</span>
Press Ctrl+C to abort.
Affect<span class="o">(</span>class-cnt:1 , method-cnt:1<span class="o">)</span> cost in <span class="m">159</span> ms.
trace com.alibaba.sample.petstore.web.store.module.screen.ItemList execute <span class="c1">#cost&gt;4</span>
<span class="sb">`</span>---thread_name<span class="o">=</span>http-nio-8080-exec-5<span class="p">;</span><span class="nv">id</span><span class="o">=</span>2c<span class="p">;</span><span class="nv">is_daemon</span><span class="o">=</span>true<span class="p">;</span><span class="nv">priority</span><span class="o">=</span><span class="m">5</span><span class="p">;</span><span class="nv">TCCL</span><span class="o">=</span>com.taobao.pandora.boot.embedded.tomcat.TomcatEmbeddedWebappClassLoader
<span class="sb">`</span>---<span class="o">[</span><span class="m">8</span>.866586ms<span class="o">]</span> com.alibaba.sample.petstore.web.store.module.screen.ItemList:execute<span class="o">()</span>
+---<span class="o">[</span><span class="m">2</span>.847106ms<span class="o">]</span> com.alibaba.sample.petstore.biz.StoreManager:getAllProductItems<span class="o">()</span>
+---<span class="o">[</span><span class="m">0</span>.765544ms<span class="o">]</span> com.alibaba.sample.petstore.dal.dao.ProductDao:getProductById<span class="o">()</span>
+---<span class="o">[</span><span class="m">0</span>.021204ms<span class="o">]</span> com.alibaba.sample.petstore.dal.dataobject.Product:getCategoryId<span class="o">()</span>
+---<span class="o">[</span><span class="m">1</span>.341532ms<span class="o">]</span> com.alibaba.sample.petstore.dal.dao.CategoryDao:getCategoryById<span class="o">()</span>
<span class="sb">`</span>---<span class="o">[</span><span class="nv">min</span><span class="o">=</span><span class="m">0</span>.005428ms,max<span class="o">=</span><span class="m">0</span>.094064ms,total<span class="o">=</span><span class="m">0</span>.105228ms,count<span class="o">=</span><span class="m">3</span><span class="o">]</span> com.alibaba.citrus.turbine.Context:put<span class="o">()</span>
</pre></div>
</div>
<blockquote>
<div>Only the call path whichs time cost is higher than <code class="docutils literal notranslate"><span class="pre">4ms</span></code> will be shown. This feature is handy to focus on whats needed to focus when troubleshoot.</div></blockquote>
<ul class="simple">
<li>Here Arthas provides the similar functionality JProfile and other commercial software provide. Compared to these professional softwares, Arthas doesnt deduce the time cost <code class="docutils literal notranslate"><span class="pre">trace</span></code> itself takes, therefore it is not as accurate as these softwares offer. More classes and methods on the calling path, more inaccurate <code class="docutils literal notranslate"><span class="pre">trace</span></code> output is, but it is still helpful for diagnostics where the bottleneck is.</li>
<li>“[2.847106ms] com.alibaba.sample.petstore.biz.StoreManager:getAllProductItems()” means “getAllProductItem()” method from “com.alibaba.sample.petstore.biz.StoreManager” takes <code class="docutils literal notranslate"><span class="pre">2.847106</span></code> ms.</li>
<li>“[min=0.005428ms,max=0.094064ms,total=0.105228ms,count=3] com.alibaba.citrus.turbine.Context:put()” means aggregating all same method calls into one single line. The minimum time cost is <code class="docutils literal notranslate"><span class="pre">0.005428</span></code> ms, the maximum time cost is <code class="docutils literal notranslate"><span class="pre">0.094064</span></code> ms, and the total time cost for all method calls (<code class="docutils literal notranslate"><span class="pre">3</span></code> times in total) to “com.alibaba.citrus.turbine.Context:put()” is <code class="docutils literal notranslate"><span class="pre">0.105228ms</span></code>. If “throws Exception” appears in this line, it means some exceptions have been thrown from this method calls.</li>
<li>The total time cost may not equal to the sum of the time costs each sub method call takes, this is because Arthas instrumented code takes time too.</li>
</ul>
</div>
</div>
</div>
</div>
<footer>
<div class="rst-footer-buttons" role="navigation" aria-label="footer navigation">
<a href="stack.html" class="btn btn-neutral float-right" title="stack" accesskey="n" rel="next">Next <span class="fa fa-arrow-circle-right"></span></a>
<a href="advice-class.html" class="btn btn-neutral" title="Fundamental Fields in Expressions" accesskey="p" rel="prev"><span class="fa fa-arrow-circle-left"></span> Previous</a>
</div>
<hr/>
<div role="contentinfo">
<p>
&copy; Copyright 2018, Alibaba Middleware Group, and contributors.
</p>
</div>
Built with <a href="http://sphinx-doc.org/">Sphinx</a> using a <a href="https://github.com/rtfd/sphinx_rtd_theme">theme</a> provided by <a href="https://readthedocs.org">Read the Docs</a>.
</footer>
</div>
</div>
</section>
</div>
<script type="text/javascript">
var DOCUMENTATION_OPTIONS = {
URL_ROOT:'./',
VERSION:'3.0.6-SNAPSHOT',
LANGUAGE:'en',
COLLAPSE_INDEX:false,
FILE_SUFFIX:'.html',
HAS_SOURCE: true,
SOURCELINK_SUFFIX: '.txt'
};
</script>
<script type="text/javascript" src="_static/jquery.js"></script>
<script type="text/javascript" src="_static/underscore.js"></script>
<script type="text/javascript" src="_static/doctools.js"></script>
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
<script type="text/javascript" src="_static/js/theme.js"></script>
<script type="text/javascript">
jQuery(function () {
SphinxRtdTheme.Navigation.enable(true);
});
</script>
<div class="github-fork-ribbon-wrapper right">
<div class="github-fork-ribbon">
<a href="https://github.com/alibaba/arthas">Fork me at GitHub</a>
</div>
</div>
<script type="text/javascript" src="_static/add_badges.js"></script>
<script>
var _hmt = _hmt || [];
(function() {
var hm = document.createElement("script");
hm.src = "https://hm.baidu.com/hm.js?d5c5e25b100f0eb51a4c35c8a86ea9b4";
var s = document.getElementsByTagName("script")[0];
s.parentNode.insertBefore(hm, s);
})();
</script>
</body>
</html>