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Updates based on GC handling changes.
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‎architecture.html‎

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<!DOCTYPE html>
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<html>
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<head>
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<meta http-equiv="content-type" content="text/html; charset=windows-1252">
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<title>ruby-prof</title>
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<link rel="stylesheet" type="text/css" href="assets/styles.css">
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</head>
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<body>
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<div class="header"><img src="./assets/ruby-prof-logo-white.svg"></div>
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<div class="grid-container">
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<nav role="navigation">
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<ul>
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<li><a href="#overview">Overview</a></li>
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<li><a href="#api-documentation">API Documentation</a></li>
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<li><a href="#license"></a><a href="#license">License</a></li>
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<li><a href="#development">Development</a></li>
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</ul>
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</nav>
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<div class="main">
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<h1>Architecuture<span> </span></h1>
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<p><a href="https://travis-ci.org/ruby-prof/ruby-prof"><img src="https://travis-ci.org/ruby-prof/ruby-prof.png?branch=master"
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alt="Build Status"></a></p>
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<h2><a id="overview">Overview</a></h2>
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<p>ruby-prof is a profiler for MRI Ruby. Its built as a C extension and
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therefore many times faster than the standard Ruby profiler. The image
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below shows the main classes that make up ruby-prof:</p>
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<p><br>
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</p>
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<img src="assets/class_diagram.png" alt="Class Diagram" title="Class Diagram">
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<p><br>
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</p>
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The top level class is Profile, which is returned by a profiling run:
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<pre class="ruby"><span class="ruby-identifier">profile = RubyProf.profile do </span><br> ..
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<span style="color: navajowhite;"> end</span></pre>
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<p>A profile owns a hash of threads, and threads in turn own the methods
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called in that thread as well as call trees which record how the
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methods were called.</p>
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<h2><a id="memory">Memory Management</a></h2>
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<p>The master object is the Profile object. Each Profile object is
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responsible for managing the memory of its child objects which are C
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structures. When the Profile object goes out of scope, it recursively
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frees all its objects.&nbsp; In the class diagram, this can bee seen
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by the composition relationships. The owning object is denoted with a
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filled in black diamond. Thus a Profile frees its threads, Threads
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free their Methods, etc.</p>
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<p><br>
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</p>
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<p><br>
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</p>
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</div>
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</div>
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</body>
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</html>
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<!DOCTYPE html>
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<html>
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<head>
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<meta http-equiv="content-type" content="text/html; charset=windows-1252">
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<title>ruby-prof</title>
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<link rel="stylesheet" type="text/css" href="assets/styles.css">
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</head>
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<body>
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<div class="header"><img src="./assets/ruby-prof-logo-white.svg"></div>
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<div class="grid-container">
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<nav role="navigation">
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<ul>
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<li><a href="#overview">Overview</a></li>
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<li><a href="#api-documentation">API Documentation</a></li>
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<li><a href="#license"></a><a href="#license">License</a></li>
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<li><a href="#development">Development</a></li>
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</ul>
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</nav>
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<div class="main">
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<h1>Architecuture<span> </span></h1>
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<p><a href="https://travis-ci.org/ruby-prof/ruby-prof"><img src="https://travis-ci.org/ruby-prof/ruby-prof.png?branch=master"
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alt="Build Status"></a></p>
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<h2><a id="overview">Overview</a></h2>
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<p>ruby-prof is a profiler for MRI Ruby. Its built as a C extension and
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therefore many times faster than the standard Ruby profiler. The image
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below shows the main classes that make up ruby-prof:</p>
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<p><br>
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</p>
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<img src="assets/class_diagram.png" alt="Class Diagram" title="Class Diagram">
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<p><br>
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</p>
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The top level class is Profile, which is returned by a profiling run:
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<pre class="ruby"><span class="ruby-identifier">profile = RubyProf.profile do </span><br> ..
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<span style="color: navajowhite;"> end</span></pre>
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<p>A profile owns a hash of threads, and threads in turn own the methods
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called in that thread as well as call trees which record how the
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methods were called.</p>
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<h2><a id="memory">Memory Management</a></h2>
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<p>The master object is the Profile object. Each Profile object is
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responsible for managing the memory of its child objects which are C
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structures. When the Profile object goes out of scope, it recursively
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frees all its objects.&nbsp; In the class diagram, this can bee seen
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via the composition relationships. The owning object is denoted with a
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filled in black diamond. Thus a Profile frees its threads, Threads
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free their CallTrees and Methods, etc.</p>
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<p>You should always keep a reference to a Profile object so that you can generate profiling
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reports. However, RubyProf will keep a Profile object alive, even if it has no direct references,
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as long as there are live references to either a MethodInfo object or a CallTree object. This is
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done via the GC mark phase. CallTree instances mark their associated MethodInfo instances, and MethodInfo
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instances in turn mark their owning Profile instance.
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</p>
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<p>Previous versions of RubyProf (before 1.3) would not keep the top level Profile instance alive and instead
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would detect when the underlying Ruby object was freed. However, this approach could result in
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crashes if a GC happened just at the wrong time. Specifically, when trying to expose an object such as
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a CallTree Ruby performs a memory allocation. This allocation could trigger a GC, freeing the top level
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Profile instance and its associated CallTree. Thus the returned CallTree instance would be invalid.
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</p>
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</div>
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</div>
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</body>
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</html>

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