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</div> <div class="document"> <div class="documentwrapper"> <div class="bodywrapper"> <div class="body" role="main"> <div class="section" id="debugging-and-profiling"> <h1>Debugging and Profiling<a class="headerlink" href="#debugging-and-profiling" title="Permalink to this headline">¶</a></h1> <p>These libraries help you with Python development: the debugger enables you to step through code, analyze stack frames and set breakpoints etc., and the profilers run code and give you a detailed breakdown of execution times, allowing you to identify bottlenecks in your programs.</p> <div class="toctree-wrapper compound"> <ul> <li class="toctree-l1"><a class="reference internal" href="bdb.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">bdb</span></code> — Debugger framework</a></li> <li class="toctree-l1"><a class="reference internal" href="faulthandler.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">faulthandler</span></code> — Dump the Python traceback</a><ul> <li class="toctree-l2"><a class="reference internal" href="faulthandler.html#dumping-the-traceback">Dumping the traceback</a></li> <li class="toctree-l2"><a class="reference internal" href="faulthandler.html#fault-handler-state">Fault handler state</a></li> <li class="toctree-l2"><a class="reference internal" href="faulthandler.html#dumping-the-tracebacks-after-a-timeout">Dumping the tracebacks after a timeout</a></li> <li class="toctree-l2"><a class="reference internal" href="faulthandler.html#dumping-the-traceback-on-a-user-signal">Dumping the traceback on a user signal</a></li> <li class="toctree-l2"><a class="reference internal" href="faulthandler.html#issue-with-file-descriptors">Issue with file descriptors</a></li> <li class="toctree-l2"><a class="reference internal" href="faulthandler.html#example">Example</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="pdb.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">pdb</span></code> — The Python Debugger</a><ul> <li class="toctree-l2"><a class="reference internal" href="pdb.html#debugger-commands">Debugger Commands</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="profile.html">The Python Profilers</a><ul> <li class="toctree-l2"><a class="reference internal" href="profile.html#introduction-to-the-profilers">Introduction to the profilers</a></li> <li class="toctree-l2"><a class="reference internal" href="profile.html#instant-user-s-manual">Instant User’s Manual</a></li> <li class="toctree-l2"><a class="reference internal" href="profile.html#module-cProfile"><code class="xref py py-mod docutils literal notranslate"><span class="pre">profile</span></code> and <code class="xref py py-mod docutils literal notranslate"><span class="pre">cProfile</span></code> Module Reference</a></li> <li class="toctree-l2"><a class="reference internal" href="profile.html#the-stats-class">The <code class="xref py py-class docutils literal notranslate"><span class="pre">Stats</span></code> Class</a></li> <li class="toctree-l2"><a class="reference internal" href="profile.html#what-is-deterministic-profiling">What Is Deterministic Profiling?</a></li> <li class="toctree-l2"><a class="reference internal" href="profile.html#limitations">Limitations</a></li> <li class="toctree-l2"><a class="reference internal" href="profile.html#calibration">Calibration</a></li> <li class="toctree-l2"><a class="reference internal" href="profile.html#using-a-custom-timer">Using a custom timer</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="timeit.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">timeit</span></code> — Measure execution time of small code snippets</a><ul> <li class="toctree-l2"><a class="reference internal" href="timeit.html#basic-examples">Basic Examples</a></li> <li class="toctree-l2"><a class="reference internal" href="timeit.html#python-interface">Python Interface</a></li> <li class="toctree-l2"><a class="reference internal" href="timeit.html#command-line-interface">Command-Line Interface</a></li> <li class="toctree-l2"><a class="reference internal" href="timeit.html#examples">Examples</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="trace.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">trace</span></code> — Trace or track Python statement execution</a><ul> <li class="toctree-l2"><a class="reference internal" href="trace.html#command-line-usage">Command-Line Usage</a><ul> <li class="toctree-l3"><a class="reference internal" href="trace.html#main-options">Main options</a></li> <li class="toctree-l3"><a class="reference internal" href="trace.html#modifiers">Modifiers</a></li> <li class="toctree-l3"><a class="reference internal" href="trace.html#filters">Filters</a></li> </ul> </li> <li class="toctree-l2"><a class="reference internal" href="trace.html#programmatic-interface">Programmatic Interface</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="tracemalloc.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">tracemalloc</span></code> — Trace memory allocations</a><ul> <li class="toctree-l2"><a class="reference internal" href="tracemalloc.html#examples">Examples</a><ul> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#display-the-top-10">Display the top 10</a></li> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#compute-differences">Compute differences</a></li> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#get-the-traceback-of-a-memory-block">Get the traceback of a memory block</a></li> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#pretty-top">Pretty top</a></li> </ul> </li> <li class="toctree-l2"><a class="reference internal" href="tracemalloc.html#api">API</a><ul> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#functions">Functions</a></li> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#domainfilter">DomainFilter</a></li> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#filter">Filter</a></li> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#frame">Frame</a></li> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#snapshot">Snapshot</a></li> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#statistic">Statistic</a></li> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#statisticdiff">StatisticDiff</a></li> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#trace">Trace</a></li> <li class="toctree-l3"><a class="reference internal" href="tracemalloc.html#traceback">Traceback</a></li> </ul> </li> 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