projects / OpenSPARC-T2-DV / blame
| Commit | Line | Data |
|---|---|---|
| 86530b38 AT |
1 | <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> |
| 2 | <html> | |
| 3 | <head> | |
| 4 | <link rel="STYLESHEET" href="lib.css" type='text/css' /> | |
| 5 | <link rel="SHORTCUT ICON" href="../icons/pyfav.png" type="image/png" /> | |
| 6 | <link rel='start' href='../index.html' title='Python Documentation Index' /> | |
| 7 | <link rel="first" href="lib.html" title='Python Library Reference' /> | |
| 8 | <link rel='contents' href='contents.html' title="Contents" /> | |
| 9 | <link rel='index' href='genindex.html' title='Index' /> | |
| 10 | <link rel='last' href='about.html' title='About this document...' /> | |
| 11 | <link rel='help' href='about.html' title='About this document...' /> | |
| 12 | <link rel="next" href="module-hotshot.html" /> | |
| 13 | <link rel="prev" href="profile-calibration.html" /> | |
| 14 | <link rel="parent" href="profile.html" /> | |
| 15 | <link rel="next" href="module-hotshot.html" /> | |
| 16 | <meta name='aesop' content='information' /> | |
| 17 | <title>10.8 Extensions -- Deriving Better Profilers</title> | |
| 18 | </head> | |
| 19 | <body> | |
| 20 | <DIV CLASS="navigation"> | |
| 21 | <div id='top-navigation-panel' xml:id='top-navigation-panel'> | |
| 22 | <table align="center" width="100%" cellpadding="0" cellspacing="2"> | |
| 23 | <tr> | |
| 24 | <td class='online-navigation'><a rel="prev" title="10.7 Calibration" | |
| 25 | href="profile-calibration.html"><img src='../icons/previous.png' | |
| 26 | border='0' height='32' alt='Previous Page' width='32' /></A></td> | |
| 27 | <td class='online-navigation'><a rel="parent" title="10. The Python Profiler" | |
| 28 | href="profile.html"><img src='../icons/up.png' | |
| 29 | border='0' height='32' alt='Up One Level' width='32' /></A></td> | |
| 30 | <td class='online-navigation'><a rel="next" title="10.9 hotshot " | |
| 31 | href="module-hotshot.html"><img src='../icons/next.png' | |
| 32 | border='0' height='32' alt='Next Page' width='32' /></A></td> | |
| 33 | <td align="center" width="100%">Python Library Reference</td> | |
| 34 | <td class='online-navigation'><a rel="contents" title="Table of Contents" | |
| 35 | href="contents.html"><img src='../icons/contents.png' | |
| 36 | border='0' height='32' alt='Contents' width='32' /></A></td> | |
| 37 | <td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png' | |
| 38 | border='0' height='32' alt='Module Index' width='32' /></a></td> | |
| 39 | <td class='online-navigation'><a rel="index" title="Index" | |
| 40 | href="genindex.html"><img src='../icons/index.png' | |
| 41 | border='0' height='32' alt='Index' width='32' /></A></td> | |
| 42 | </tr></table> | |
| 43 | <div class='online-navigation'> | |
| 44 | <b class="navlabel">Previous:</b> | |
| 45 | <a class="sectref" rel="prev" href="profile-calibration.html">10.7 Calibration</A> | |
| 46 | <b class="navlabel">Up:</b> | |
| 47 | <a class="sectref" rel="parent" href="profile.html">10. The Python Profiler</A> | |
| 48 | <b class="navlabel">Next:</b> | |
| 49 | <a class="sectref" rel="next" href="module-hotshot.html">10.9 hotshot </A> | |
| 50 | </div> | |
| 51 | <hr /></div> | |
| 52 | </DIV> | |
| 53 | <!--End of Navigation Panel--> | |
| 54 | ||
| 55 | <H1><A NAME="SECTION0012800000000000000000"> | |
| 56 | 10.8 Extensions -- Deriving Better Profilers</A> | |
| 57 | </H1> | |
| 58 | <A NAME="Profiler_Extensions"></A> | |
| 59 | <P> | |
| 60 | The <tt class="class">Profile</tt> class of module <tt class="module">profile</tt> was written so that | |
| 61 | derived classes could be developed to extend the profiler. The details | |
| 62 | are not described here, as doing this successfully requires an expert | |
| 63 | understanding of how the <tt class="class">Profile</tt> class works internally. Study | |
| 64 | the source code of module <tt class="module">profile</tt> carefully if you want to | |
| 65 | pursue this. | |
| 66 | ||
| 67 | <P> | |
| 68 | If all you want to do is change how current time is determined (for | |
| 69 | example, to force use of wall-clock time or elapsed process time), | |
| 70 | pass the timing function you want to the <tt class="class">Profile</tt> class | |
| 71 | constructor: | |
| 72 | ||
| 73 | <P> | |
| 74 | <div class="verbatim"><pre> | |
| 75 | pr = profile.Profile(your_time_func) | |
| 76 | </pre></div> | |
| 77 | ||
| 78 | <P> | |
| 79 | The resulting profiler will then call <code>your_time_func()</code>. | |
| 80 | The function should return a single number, or a list of | |
| 81 | numbers whose sum is the current time (like what <tt class="function">os.times()</tt> | |
| 82 | returns). If the function returns a single time number, or the list of | |
| 83 | returned numbers has length 2, then you will get an especially fast | |
| 84 | version of the dispatch routine. | |
| 85 | ||
| 86 | <P> | |
| 87 | Be warned that you should calibrate the profiler class for the | |
| 88 | timer function that you choose. For most machines, a timer that | |
| 89 | returns a lone integer value will provide the best results in terms of | |
| 90 | low overhead during profiling. (<tt class="function">os.times()</tt> is | |
| 91 | <em>pretty</em> bad, as it returns a tuple of floating point values). If | |
| 92 | you want to substitute a better timer in the cleanest fashion, | |
| 93 | derive a class and hardwire a replacement dispatch method that best | |
| 94 | handles your timer call, along with the appropriate calibration | |
| 95 | constant. | |
| 96 | ||
| 97 | <DIV CLASS="navigation"> | |
| 98 | <div class='online-navigation'> | |
| 99 | <p></p><hr /> | |
| 100 | <table align="center" width="100%" cellpadding="0" cellspacing="2"> | |
| 101 | <tr> | |
| 102 | <td class='online-navigation'><a rel="prev" title="10.7 Calibration" | |
| 103 | href="profile-calibration.html"><img src='../icons/previous.png' | |
| 104 | border='0' height='32' alt='Previous Page' width='32' /></A></td> | |
| 105 | <td class='online-navigation'><a rel="parent" title="10. The Python Profiler" | |
| 106 | href="profile.html"><img src='../icons/up.png' | |
| 107 | border='0' height='32' alt='Up One Level' width='32' /></A></td> | |
| 108 | <td class='online-navigation'><a rel="next" title="10.9 hotshot " | |
| 109 | href="module-hotshot.html"><img src='../icons/next.png' | |
| 110 | border='0' height='32' alt='Next Page' width='32' /></A></td> | |
| 111 | <td align="center" width="100%">Python Library Reference</td> | |
| 112 | <td class='online-navigation'><a rel="contents" title="Table of Contents" | |
| 113 | href="contents.html"><img src='../icons/contents.png' | |
| 114 | border='0' height='32' alt='Contents' width='32' /></A></td> | |
| 115 | <td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png' | |
| 116 | border='0' height='32' alt='Module Index' width='32' /></a></td> | |
| 117 | <td class='online-navigation'><a rel="index" title="Index" | |
| 118 | href="genindex.html"><img src='../icons/index.png' | |
| 119 | border='0' height='32' alt='Index' width='32' /></A></td> | |
| 120 | </tr></table> | |
| 121 | <div class='online-navigation'> | |
| 122 | <b class="navlabel">Previous:</b> | |
| 123 | <a class="sectref" rel="prev" href="profile-calibration.html">10.7 Calibration</A> | |
| 124 | <b class="navlabel">Up:</b> | |
| 125 | <a class="sectref" rel="parent" href="profile.html">10. The Python Profiler</A> | |
| 126 | <b class="navlabel">Next:</b> | |
| 127 | <a class="sectref" rel="next" href="module-hotshot.html">10.9 hotshot </A> | |
| 128 | </div> | |
| 129 | </div> | |
| 130 | <hr /> | |
| 131 | <span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span> | |
| 132 | </DIV> | |
| 133 | <!--End of Navigation Panel--> | |
| 134 | <ADDRESS> | |
| 135 | See <i><a href="about.html">About this document...</a></i> for information on suggesting changes. | |
| 136 | </ADDRESS> | |
| 137 | </BODY> | |
| 138 | </HTML> |