The execs at my company want a similar 'snapshot'. Essentially I create a graph showing usage in 15 minute intervals. For every log entry I parse the session and date. I convert the date like below: 
for($date){
   ($h,$m,$s)=split/:/;
   s/\:\d\d$//;  #throw out the seconds, we don't need them
   $m="00" if ($m<15);
   $m="15" if (($m>=15) && ($m<30));
   $m="30" if (($m>=30) && ($m<45));
   $m="45" if ($m>=45);
   s/\:\d\d\/\:$m/; #replace the minutes with the generalized value
}

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Now I create a hash with the key values equal to a the generalized timestamp. This lets me see how many unique sessions were active during a given 15 minute interval: 
$parseddata{$date}++ unless grep{$_ eq "$date|$session"}@seen;
push @seen,"$date|$session";

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Now I have a hash with keys equal to 15 minute interval timestamps and values equal to the number of unique sessions active during the interval. I then create the graph: 
my @keys = sort keys %parseddata;
my @values;
for(@keys){
 push @values,$parseddata{$_};
}
my @data=([@keys],[@values]);
my $graph=GD::Graph::area->new(1000,600);
#set all the graph options(labels, colors etc...)
my $gd = $graph->plot(\@data);
open(GRAPH, ">/graphs/$datestamp.png) or die "Can't open output file f
+or graph: $!";
binmode GRAPH;
print GRAPH $gd->png;

[download]

In reply to Re: How to do session times The Right Way by insensate
in thread How to do session times The Right Way by strider corinth

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