Add lib/, t/lib/, and sandbox/. All modules are updated and passing on MySQL 5.1.

lib/TimeSeriesTrender.pm

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+# This program is copyright 2010-2011 Percona Inc.
+# 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.
+# ###########################################################################
+# TimeSeriesTrender package $Revision: 7096 $
+# ###########################################################################
+
+# Package: TimeSeriesTrender
+# TimeSeriesTrender calculates trends in time.
+{
+package TimeSeriesTrender;
+
+use strict;
+use warnings FATAL => 'all';
+use English qw(-no_match_vars);
+use constant MKDEBUG => $ENV{MKDEBUG} || 0;
+
+# Arguments:
+#  *  callback    Subroutine to call when the time is set to the next larger
+#                 increment.  Receives a hashref of the current timestamp's
+#                 stats (see compute_stats()).
+sub new {
+   my ( $class, %args ) = @_;
+   foreach my $arg ( qw(callback) ) {
+      die "I need a $arg argument" unless defined $args{$arg};
+   }
+   my $self = {
+      %args,
+      ts      => '',
+      numbers => [],
+   };
+   return bless $self, $class;
+}
+
+# Set the current timestamp to be applied to all subsequent values received
+# through add_number().  If the timestamp changes to the "next larger
+# increment," then fire the callback.  It *is* possible for a timestamp to be
+# less than one previously seen.  In such cases, we simply lump those
+# time-series data points into the current timestamp's bucket.
+sub set_time {
+   my ( $self, $ts ) = @_;
+   my $cur_ts = $self->{ts};
+   if ( !$cur_ts ) {
+      $self->{ts} = $ts;
+   }
+   elsif ( $ts gt $cur_ts ) {
+      my $statistics = $self->compute_stats($cur_ts, $self->{numbers});
+      $self->{callback}->($statistics);
+      $self->{numbers} = [];
+      $self->{ts}      = $ts;
+   }
+   # If $cur_ts > $ts, then we do nothing -- we do not want $self->{ts} to ever
+   # decrease!
+}
+
+# Add a number to the current batch defined by the current timestamp, which is
+# set by set_time().
+sub add_number {
+   my ( $self, $number ) = @_;
+   push @{$self->{numbers}}, $number;
+}
+
+# Compute the desired statistics over the set of numbers, which is passed in as
+# an arrayref.  Returns a hashref.
+sub compute_stats {
+   my ( $self, $ts, $numbers ) = @_;
+   my $cnt = scalar @$numbers;
+   my $result = {
+      ts    => $ts,
+      cnt   => 0,
+      sum   => 0,
+      min   => 0,
+      max   => 0,
+      avg   => 0,
+      stdev => 0,
+   };
+   return $result unless $cnt;
+   my ( $sum, $min, $max, $sumsq ) = (0, 2 ** 32, 0, 0);
+   foreach my $num ( @$numbers ) {
+      $sum   += $num;
+      $min    = $num < $min ? $num : $min;
+      $max    = $num > $max ? $num : $max;
+      $sumsq += $num * $num;
+   }
+   my $avg   = $sum / $cnt;
+   my $var   = $sumsq / $cnt - ( $avg * $avg );
+   my $stdev = $var > 0 ? sqrt($var) : 0;
+   # TODO: must compute the significant digits of the input, and use that to
+   # round the output appropriately.
+   @{$result}{qw(cnt sum min max avg stdev)}
+      = ($cnt, $sum, $min, $max, $avg, $stdev);
+   return $result;
+}
+
+sub _d {
+   my ($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 TimeSeriesTrender package
+# ###########################################################################