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\section{\module{hotshot} ---         High performance logging profiler} \declaremodule{standard}{hotshot}\modulesynopsis{High performance logging profiler, mostly written in C.}\moduleauthor{Fred L. Drake, Jr.}{fdrake@acm.org}\sectionauthor{Anthony Baxter}{anthony@interlink.com.au} \versionadded{2.2}  This module provides a nicer interface to the \module{_hotshot} C module.Hotshot is a replacement for the existing \refmodule{profile} module. As it'swritten mostly in C, it should result in a much smaller performance impactthan the existing \refmodule{profile} module. \begin{notice}[note]  The \module{hotshot} module focuses on minimizing the overhead  while profiling, at the expense of long data post-processing times.  For common usages it is recommended to use \module{cProfile} instead.  \module{hotshot} is not maintained and might be removed from the  standard library in the future.\end{notice} \versionchanged[the results should be more meaningful than in thepast: the timing core contained a critical bug]{2.5} \begin{notice}[warning]  The \module{hotshot} profiler does not yet work well with threads.  It is useful to use an unthreaded script to run the profiler over  the code you're interested in measuring if at all possible.\end{notice}  \begin{classdesc}{Profile}{logfile\optional{, lineevents\optional{,                           linetimings}}}The profiler object. The argument \var{logfile} is the name of a logfile to use for logged profile data. The argument \var{lineevents}specifies whether to generate events for every source line, or just onfunction call/return. It defaults to \code{0} (only log functioncall/return). The argument \var{linetimings} specifies whether torecord timing information. It defaults to \code{1} (store timinginformation).\end{classdesc}  \subsection{Profile Objects \label{hotshot-objects}} Profile objects have the following methods: \begin{methoddesc}{addinfo}{key, value}Add an arbitrary labelled value to the profile output.\end{methoddesc} \begin{methoddesc}{close}{}Close the logfile and terminate the profiler.\end{methoddesc} \begin{methoddesc}{fileno}{}Return the file descriptor of the profiler's log file.\end{methoddesc} \begin{methoddesc}{run}{cmd}Profile an \keyword{exec}-compatible string in the script environment.The globals from the \refmodule[main]{__main__} module are used asboth the globals and locals for the script.\end{methoddesc} \begin{methoddesc}{runcall}{func, *args, **keywords}Profile a single call of a callable.Additional positional and keyword arguments may be passedalong; the result of the call is returned, and exceptions areallowed to propagate cleanly, while ensuring that profiling isdisabled on the way out.\end{methoddesc}  \begin{methoddesc}{runctx}{cmd, globals, locals}Evaluate an \keyword{exec}-compatible string in a specific environment.The string is compiled before profiling begins.\end{methoddesc} \begin{methoddesc}{start}{}Start the profiler.\end{methoddesc} \begin{methoddesc}{stop}{}Stop the profiler.\end{methoddesc}  \subsection{Using hotshot data} \declaremodule{standard}{hotshot.stats}\modulesynopsis{Statistical analysis for Hotshot} \versionadded{2.2} This module loads hotshot profiling data into the standard \module{pstats}Stats objects. \begin{funcdesc}{load}{filename}Load hotshot data from \var{filename}. Returns an instanceof the \class{pstats.Stats} class.\end{funcdesc} \begin{seealso}  \seemodule{profile}{The \module{profile} module's \class{Stats} class}\end{seealso}  \subsection{Example Usage \label{hotshot-example}} Note that this example runs the python ``benchmark'' pystones.  It cantake some time to run, and will produce large output files. \begin{verbatim}>>> import hotshot, hotshot.stats, test.pystone>>> prof = hotshot.Profile("stones.prof")>>> benchtime, stones = prof.runcall(test.pystone.pystones)>>> prof.close()>>> stats = hotshot.stats.load("stones.prof")>>> stats.strip_dirs()>>> stats.sort_stats('time', 'calls')>>> stats.print_stats(20)         850004 function calls in 10.090 CPU seconds    Ordered by: internal time, call count    ncalls  tottime  percall  cumtime  percall filename:lineno(function)        1    3.295    3.295   10.090   10.090 pystone.py:79(Proc0)   150000    1.315    0.000    1.315    0.000 pystone.py:203(Proc7)    50000    1.313    0.000    1.463    0.000 pystone.py:229(Func2) . . .\end{verbatim}