mirror of
https://github.com/percona/percona-toolkit.git
synced 2025-09-01 18:25:59 +00:00
103 lines
3.3 KiB
Perl
103 lines
3.3 KiB
Perl
# This program is copyright 2011 Percona Ireland Ltd.
|
|
# Feedback and improvements are welcome.
|
|
#
|
|
# THIS PROGRAM IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
|
|
# WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
|
|
# MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
|
#
|
|
# This program is free software; you can redistribute it and/or modify it under
|
|
# the terms of the GNU General Public License as published by the Free Software
|
|
# Foundation, version 2; OR the Perl Artistic License. On UNIX and similar
|
|
# systems, you can issue `man perlgpl' or `man perlartistic' to read these
|
|
# licenses.
|
|
#
|
|
# You should have received a copy of the GNU General Public License along with
|
|
# this program; if not, write to the Free Software Foundation, Inc., 59 Temple
|
|
# Place, Suite 330, Boston, MA 02111-1307 USA.
|
|
# ###########################################################################
|
|
# WeightedAvgRate package
|
|
# ###########################################################################
|
|
{
|
|
# Package: WeightedAvgRate
|
|
# WeightedAvgRate calculates and returns a weighted average rate.
|
|
package WeightedAvgRate;
|
|
|
|
use strict;
|
|
use warnings FATAL => 'all';
|
|
use English qw(-no_match_vars);
|
|
use constant PTDEBUG => $ENV{PTDEBUG} || 0;
|
|
|
|
# Sub: new
|
|
#
|
|
# Required Arguments:
|
|
# target_t - Target time for t in <update()>
|
|
#
|
|
# Optional Arguments:
|
|
# weight - Weight of previous n/t values (default 0.75).
|
|
#
|
|
# Returns:
|
|
# WeightedAvgRate
|
|
sub new {
|
|
my ( $class, %args ) = @_;
|
|
my @required_args = qw(target_t);
|
|
foreach my $arg ( @required_args ) {
|
|
die "I need a $arg argument" unless defined $args{$arg};
|
|
}
|
|
|
|
my $self = {
|
|
%args,
|
|
avg_n => 0,
|
|
avg_t => 0,
|
|
weight => $args{weight} || 0.75,
|
|
};
|
|
|
|
return bless $self, $class;
|
|
}
|
|
|
|
# Sub: update
|
|
# Update weighted average rate. Param n is generic; it's how many of
|
|
# whatever the caller is doing (rows, checksums, etc.). Param s is how
|
|
# long this n took, in seconds (hi-res or not).
|
|
#
|
|
# Parameters:
|
|
# n - Number of operations (rows, etc.)
|
|
# t - Amount of time in seconds that n took
|
|
#
|
|
# Returns:
|
|
# n adjust to meet target_t based on weighted decaying avg rate
|
|
sub update {
|
|
my ($self, $n, $t) = @_;
|
|
PTDEBUG && _d('Source op time:', $n, 'n /', $t, 's');
|
|
|
|
if ( $self->{avg_n} && $self->{avg_t} ) {
|
|
$self->{avg_n} = ($self->{avg_n} * $self->{weight}) + $n;
|
|
$self->{avg_t} = ($self->{avg_t} * $self->{weight}) + $t;
|
|
$self->{avg_rate} = $self->{avg_n} / $self->{avg_t};
|
|
PTDEBUG && _d('Weighted avg rate:', $self->{avg_rate}, 'n/s');
|
|
}
|
|
else {
|
|
$self->{avg_n} = $n;
|
|
$self->{avg_t} = $t;
|
|
$self->{avg_rate} = $self->{avg_n} / $self->{avg_t};
|
|
PTDEBUG && _d('Initial avg rate:', $self->{avg_rate}, 'n/s');
|
|
}
|
|
|
|
my $new_n = int($self->{avg_rate} * $self->{target_t});
|
|
PTDEBUG && _d('Adjust n to', $new_n);
|
|
return $new_n;
|
|
}
|
|
|
|
sub _d {
|
|
my ($package, undef, $line) = caller 0;
|
|
@_ = map { (my $temp = $_) =~ s/\n/\n# /g; $temp; }
|
|
map { defined $_ ? $_ : 'undef' }
|
|
@_;
|
|
print STDERR "# $package:$line $PID ", join(' ', @_), "\n";
|
|
}
|
|
|
|
1;
|
|
}
|
|
# ###########################################################################
|
|
# End WeightedAvgRate package
|
|
# ###########################################################################
|