-# Devel::DProf - a Perl code profiler
-# 5apr95
-# Dean Roehrich
-#
-# changes/bugs fixed since 01mar95 version:
-# - record $pwd and build pathname for tmon.out
-# (so the profile doesn't get lost if the process chdir's)
-# changes/bugs fixed since 03feb95 version:
-# - fixed some doc bugs
-# - added require 5.000
-# - added -w note to bugs section of pod
-# changes/bugs fixed since 31dec94 version:
-# - podified
-#
-
-require 5.000;
+use 5.006_001;
=head1 NAME
=head1 SYNOPSIS
- PERL5DB="use Devel::DProf;"
- export PERL5DB
-
- perl5 -d test.pl
+ perl5 -d:DProf test.pl
=head1 DESCRIPTION
information can also be used to create an execution graph of the script,
showing subroutine relationships.
-To use this package the PERL5DB environment variable must be set to the
-following value:
-
- PERL5DB="use Devel::DProf;"
- export PERL5DB
-
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
-"test.pl" the following command should be used:
+F<test.pl> the following command should be used:
- perl5 -d test.pl
+ perl5 -d:DProf test.pl
-When the script terminates the profiler will dump the profile information
-to a file called I<tmon.out>. The supplied I<dprofpp> tool 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:
+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
dprofpp -T
-Consult the "dprofpp" manpage for other options.
+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
-If perl5 is invoked with the B<-w> (warnings) flag then Devel::DProf will
-cause a large quantity of warnings to be printed.
+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 = $DB::sub + 0;
+
+will set this numeric slot to numeric value of the string
+C<current_sub>, i.e., to C<0>. This will cause a segfault on the exit
+from this subroutine. Note that the first assignment above does not
+change the numeric slot (it will I<mark> it as invalid, but will not
+write over it).
+
+Another problem is that if a subroutine exits using goto(LABEL),
+last(LABEL) or next(LABEL) then perl may crash or Devel::DProf will die
+with the error:
+
+ panic: Devel::DProf inconsistent subroutine return
+
+For example, this code will break under Devel::DProf:
+
+ sub foo {
+ last FOO;
+ }
+ FOO: {
+ foo();
+ }
+
+A pattern like this is used by Test::More's skip() function, for
+example. See L<perldiag> for more details.
+
+Mail bug reports and feature requests to the perl5-porters mailing list at
+F<E<lt>perl5-porters@perl.orgE<gt>>.
=head1 SEE ALSO
=cut
-package DB;
+# This sub is needed for calibration.
+package Devel::DProf;
-# So Devel::DProf knows where to drop tmon.out.
-chop($pwd = `pwd`);
-$tmon = "$pwd/tmon.out";
-
-# This sub is replaced by an XS version after the profiler is bootstrapped.
-sub sub {
-# print "nonXS DBsub($sub)\n";
- $single = 0; # disable DB single-stepping
- if( wantarray ){
- @a = &$sub;
- @a;
- }
- else{
- $a = &$sub;
- $a;
- }
+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 { $single = 0; }
+
# This sub is needed during startup.
sub DB {
# print "nonXS DBDB\n";
}
+use XSLoader ();
-require DynaLoader;
-@Devel::DProf::ISA = qw(DynaLoader);
+# Underscore to allow older Perls to access older version from CPAN
+$Devel::DProf::VERSION = '20030108.00_00'; # this version not authorized by
+ # Dean Roehrich. See "Changes" file.
-bootstrap Devel::DProf;
+XSLoader::load 'Devel::DProf', $Devel::DProf::VERSION;
1;