NAME
Benchmark::Stopwatch - simple timing of stages of your code.
SYNOPSIS
use Benchmark::Stopwatch;
my $stopwatch = Benchmark::Stopwatch->new->start;
# ... code that reads from database ...
$stopwatch->lap('read from database');
# ... code that writes to disk ...
$stopwatch->lap('write to disk');
print $stopwatch->stop->summary;
# NAME TIME CUMULATIVE PERCENTAGE
# read from database 0.123 0.123 34.462%
# write to disk 0.234 0.357 65.530%
# _stop_ 0.000 0.357 0.008%
DESCRIPTION
The other benchmark modules provide excellent timing for specific parts of your code. This module aims to allow you to easily time the progression of your code.
The stopwatch analogy is that at some point you get a new
stopwatch and start
timing. Then you note certain events using lap
. Finally you stop
the watch and then print out a summary
.
The summary shows all the events in order, what time they occured at, how long since the last lap and the percentage of the total time. Hopefully this will give you a good idea of where your code is spending most of its time.
The times are all wallclock times in fractional seconds.
That's it.
METHODS
new
my $stopwatch = Benchmark::Stopwatch->new;
Creates a new stopwatch.
start
$stopwatch = $stopwatch->start;
Starts the stopwatch. Returns a reference to the stopwatch so that you can chain.
lap
$stopwatch = $stopwatch->lap( 'name of event' );
Notes down the time at which an event occurs. This event will later appear in the summary.
stop
$stopwatch = $stopwatch->stop;
Stops the stopwatch. Returns a reference to the stopwatch so you can chain.
total_time
my $time_in_seconds = $stopwatch->total_time;
Returns the time that the stopwatch ran for in fractional seconds. If the stopwatch has not been stopped yet then it returns time it has been running for.
summary
my $summary_text = $stopwatch->summary;
Returns text summarizing the events that occured. Example output from a script that fetches the homepages of the web's five busiest sites and times how long each took.
NAME TIME CUMULATIVE PERCENTAGE
http://www.yahoo.com/ 3.892 3.892 22.399%
http://www.google.com/ 3.259 7.152 18.758%
http://www.msn.com/ 8.412 15.564 48.411%
http://www.myspace.com/ 0.532 16.096 3.062%
http://www.ebay.com/ 1.281 17.377 7.370%
_stop_ 0.000 17.377 0.000%
The final entry _stop_
is when the stop watch was stopped.
as_data
my $data_structure_hashref = $stopwatch->as_data;
Returns a data structure that contains all the information that was logged. This is so that you can use this module to gather the data but then use your own code to manipulate it.
The returned hashref will look like this:
{
start_time => 1234500, # The time the stopwatch was started
stop_time => 1234510, # The time it was stopped or as_data called
total_time => 10, # The duration of timing
laps => [
{
name => 'test', # The name of the lap
time => 1, # The time of this lap (seconds)
cumulative => 1, # seconds since start to this lap
fraction => 0.10, # fraction of total time.
},
{
name => '_stop_', # created as needed
time => 9,
cumulative => 10,
fraction => 0.9,
},
],
}
AUTHOR
Edmund von der Burg <evdb@ecclestoad.co.uk
>
ACKNOWLEDGMENTS
Inspiration from my colleagues at http://www.nestoria.co.uk
COPYRIGHT
Copyright (C) 2006 Edmund von der Burg. All rights reserved.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. If it breaks you get to keep both pieces.
THERE IS NO WARRANTY.