DashProfiler::Auto - Creates and imports a predeclared DashProfiler sampler
Measure the time spent between creating a sample object and destroying it:
$ perl -MDashProfiler::Auto -w -e '$a=auto_profiler("foobar"); sleep 1; undef $a'
auto > -e > foobar: dur=1.000231 count=1 (max=1.000231 avg=1.000231)
auto > other > other: dur=0.000451 count=1 (max=0.000451 avg=0.000451)
The leading "auto > -e > foobar" portion shows the name of the profiler (auto), the name of the file that called it (in this case "-e" because the code was given on the command line), and finally the argument given to auto_profiler().
The time shown as "auto > other > other" is all the 'other' time spent by the program that isn't included in the samples taken.
This next example shows use of the 'context2' parameter to auto_profiler() and also how to samples can overlap:
$ perl -MDashProfiler::Auto -w -e '
sub fib {
my $n = shift;
return $n if $n < 2;
my $s = auto_profiler($n, undef, 1);
fib($n-1) + fib($n-2);
}
fib(7)
'
auto > -e > 2: dur=0.000054 count=8 (max=0.000013 avg=0.000002)
auto > -e > 3: dur=0.000137 count=5 (max=0.000046 avg=0.000009)
auto > -e > 4: dur=0.000197 count=3 (max=0.000085 avg=0.000028)
auto > -e > 5: dur=0.000245 count=2 (max=0.000139 avg=0.000069)
auto > -e > 6: dur=0.000226 count=1 (max=0.000226 avg=0.000226)
auto > -e > 7: dur=0.000370 count=1 (max=0.000370 avg=0.000370)
The timing for "other" isn't shown because if any samples do overlap then the period_exclusive summary is disabled.
The DashProfiler::Auto is designed for quick temporary use of DashProfiler. It avoids the need to create a profile by creating one for you with a typical configuration, and defining a sample period from the time the module was loaded to the time the program exits.
The default configuration is:
my $auto = DashProfiler->add_profile( auto => {
period_exclusive => 'other',
flush_hook => sub {
my ($self, $dbi_profile_name) = @_;
warn $_ for $self->profile_as_text($dbi_profile_name);
return $self->reset_profile_data($dbi_profile_name);
},
});
* period_exclusive enables the automatic addition of a sample which measures the time not accounted for by the samples. See "Sample Periods" below.
* flush_hook uses warn() to write out the profile data, then resets (discards) the data.
When the modle is loaded it creates the auto profile and calls
$auto->start_sample_period();
It also defines an END block which does
$auto->end_sample_period();
$auto->flush;
so the sample period runs from the time the module was loaded (typically when the program started running) through to the time the program exits.
Using DashProfile::Auto in a file like this:
use DashProfiler::Auto;
is almost identical to this:
use DashProfiler::Import auto_profiler => [ basename(__FILE__) ];
