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Diffstat (limited to 'contrib/perl5/ext/Devel/DProf/DProf.pm')
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diff --git a/contrib/perl5/ext/Devel/DProf/DProf.pm b/contrib/perl5/ext/Devel/DProf/DProf.pm new file mode 100644 index 0000000..38082fc --- /dev/null +++ b/contrib/perl5/ext/Devel/DProf/DProf.pm @@ -0,0 +1,196 @@ +require 5.005_64; + +=head1 NAME + +Devel::DProf - a Perl code profiler + +=head1 SYNOPSIS + + perl5 -d:DProf test.pl + +=head1 DESCRIPTION + +The Devel::DProf package is a Perl code profiler. This will collect +information on the execution time of a Perl script and of the subs in that +script. This information can be used to determine which subroutines are +using the most time and which subroutines are being called most often. This +information can also be used to create an execution graph of the script, +showing subroutine relationships. + +To profile a Perl script run the perl interpreter with the B<-d> debugging +switch. The profiler uses the debugging hooks. So to profile script +F<test.pl> the following command should be used: + + perl5 -d:DProf test.pl + +When the script terminates (or when the output buffer is filled) the +profiler will dump the profile information to a file called +F<tmon.out>. A tool like I<dprofpp> can be used to interpret the +information which is in that profile. The following command will +print the top 15 subroutines which used the most time: + + dprofpp + +To print an execution graph of the subroutines in the script use the +following command: + + dprofpp -T + +Consult L<dprofpp> for other options. + +=head1 PROFILE FORMAT + +The old profile is a text file which looks like this: + + #fOrTyTwO + $hz=100; + $XS_VERSION='DProf 19970606'; + # All values are given in HZ + $rrun_utime=2; $rrun_stime=0; $rrun_rtime=7 + PART2 + + 26 28 566822884 DynaLoader::import + - 26 28 566822884 DynaLoader::import + + 27 28 566822885 main::bar + - 27 28 566822886 main::bar + + 27 28 566822886 main::baz + + 27 28 566822887 main::bar + - 27 28 566822888 main::bar + [....] + +The first line is the magic number. The second line is the hertz value, or +clock ticks, of the machine where the profile was collected. The third line +is the name and version identifier of the tool which created the profile. +The fourth line is a comment. The fifth line contains three variables +holding the user time, system time, and realtime of the process while it was +being profiled. The sixth line indicates the beginning of the sub +entry/exit profile section. + +The columns in B<PART2> are: + + sub entry(+)/exit(-) mark + app's user time at sub entry/exit mark, in ticks + app's system time at sub entry/exit mark, in ticks + app's realtime at sub entry/exit mark, in ticks + fully-qualified sub name, when possible + +With newer perls another format is used, which may look like this: + + #fOrTyTwO + $hz=10000; + $XS_VERSION='DProf 19971213'; + # All values are given in HZ + $over_utime=5917; $over_stime=0; $over_rtime=5917; + $over_tests=10000; + $rrun_utime=1284; $rrun_stime=0; $rrun_rtime=1284; + $total_marks=6; + + PART2 + @ 406 0 406 + & 2 main bar + + 2 + @ 456 0 456 + - 2 + @ 1 0 1 + & 3 main baz + + 3 + @ 141 0 141 + + 2 + @ 141 0 141 + - 2 + @ 1 0 1 + & 4 main foo + + 4 + @ 142 0 142 + + & Devel::DProf::write + @ 5 0 5 + - & Devel::DProf::write + +(with high value of $ENV{PERL_DPROF_TICKS}). + +New C<$over_*> values show the measured overhead of making $over_tests +calls to the profiler These values are used by the profiler to +subtract the overhead from the runtimes. + +The lines starting with C<@> mark time passed from the previous C<@> +line. The lines starting with C<&> introduce new subroutine I<id> and +show the package and the subroutine name of this id. Lines starting +with C<+>, C<-> and C<*> mark entering and exit of subroutines by +I<id>s, and C<goto &subr>. + +The I<old-style> C<+>- and C<->-lines are used to mark the overhead +related to writing to profiler-output file. + +=head1 AUTOLOAD + +When Devel::DProf finds a call to an C<&AUTOLOAD> subroutine it looks at the +C<$AUTOLOAD> variable to find the real name of the sub being called. See +L<perlsub/"Autoloading">. + +=head1 ENVIRONMENT + +C<PERL_DPROF_BUFFER> sets size of output buffer in words. Defaults to 2**14. + +C<PERL_DPROF_TICKS> sets number of ticks per second on some systems where +a replacement for times() is used. Defaults to the value of C<HZ> macro. + +C<PERL_DPROF_OUT_FILE_NAME> sets the name of the output file. If not set, +defaults to tmon.out. + +=head1 BUGS + +Builtin functions cannot be measured by Devel::DProf. + +With a newer Perl DProf relies on the fact that the numeric slot of +$DB::sub contains an address of a subroutine. Excessive manipulation +of this variable may overwrite this slot, as in + + $DB::sub = 'current_sub'; + ... + $addr = $DB::sub + 0; + +will set this numeric slot to numeric value of the string +C<current_sub>, i.e., to C<0>. This will cause a segfault on the exit +from this subroutine. Note that the first assignment above does not +change the numeric slot (it will I<mark> it as invalid, but will not +write over it). + +Mail bug reports and feature requests to the perl5-porters mailing list at +F<E<lt>perl5-porters@perl.orgE<gt>>. + +=head1 SEE ALSO + +L<perl>, L<dprofpp>, times(2) + +=cut + +# This sub is needed for calibration. +package Devel::DProf; + +sub NONESUCH_noxs { + return $Devel::DProf::VERSION; +} + +package DB; + +# +# As of perl5.003_20, &DB::sub stub is not needed (some versions +# even had problems if stub was redefined with XS version). +# + +# disable DB single-stepping +BEGIN { $single = 0; } + +# This sub is needed during startup. +sub DB { +# print "nonXS DBDB\n"; +} + +use XSLoader (); + +# Underscore to allow older Perls to access older version from CPAN +$Devel::DProf::VERSION = '20000000.00_00'; # this version not authorized by + # Dean Roehrich. See "Changes" file. + +XSLoader::load 'Devel::DProf', $Devel::DProf::VERSION; + +1; |
