The Perl Toolchain Summit 2025 Needs You: You can help 🙏 Learn more

MELO / Proc-CPUUsage-1.002 / lib / Proc / CPUUsage.pm 

            

              
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
—
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111

              
package Proc::CPUUsage;
$Proc::CPUUsage::VERSION = '1.002';
use strict;
use warnings;
use BSD::Resource qw( getrusage );
use Time::HiRes qw( gettimeofday tv_interval );
sub new {
  my $class = shift;
   
  return bless [ [gettimeofday()], _cpu_time(), 0 ], $class;
}
sub usage {
  my $self = $_[0];
  my ($t0, $r0, $u0) = @$self;
  return unless defined $r0;
   
  my ($dt, $dr, $t1, $r1, $u1);
  $t1 = [gettimeofday()];
  $dt = tv_interval($t0, $t1);
  $self->[0] = $t1;
   
  $r1 = _cpu_time();
  $dr = $r1 - $r0;
  $self->[1] = $r1;
  $u1 = $dt == 0 ? $u0 : $dr/$dt;
  $self->[2] = $u1;
  return $u1;
}
sub _cpu_time {
  my ($utime, $stime) = getrusage();
  return unless defined $utime && defined $stime;
  return $utime+$stime;
}
1;
__END__
=encoding utf8
=head1 NAME
Proc::CPUUsage - measures the percentage of CPU the current process is using
=head1 VERSION
version 1.002
=head1 SYNOPSIS
    my $cpu = Proc::CPUUsage->new;
    my $usage1 = $cpu->usage; ## returns usage since new()
    my $usage2 = $cpu->usage; ## returns usage since last usage()
    ...
=head1 DESCRIPTION
This module allows you to measure how much CPU your perl process is
using.
The construction of the object defines the inital values. Each call to
L</"usage()"> returns the CPU usage since the last call to L</"new()"> or
L</"usage()">.
The value returned is normalised between 0 and 1, the latter being
100% usage.
=head1 METHODS
=head2 new()
    $cpu = Proc::CPUUsage->new()
Creates a new L<Proc::CPUUsage|Proc::CPUUsage> object with the current values for CPU usage.
=head2 usage()
    $usage = $cpu->usage()
Returns the CPU usage since the last call to L</"new()"> or L</"usage()">.
The value returned is greater than 0 and lower or equal to 1.
=head1 SEE ALSO
L<AnyEvent::Monitor::CPU|AnyEvent::Monitor::CPU> for a more practical use for this module.
=head1 AUTHOR
Pedro Melo, C<< <melo at cpan.org> >>
=head1 COPYRIGHT & LICENSE
Copyright 2009 Pedro Melo.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
=cut