Wow! I didn't expect so many answers so quickly!
I haven't had time to read them all but I found what was slowing it down so much:
the print command on its way to the browser
Here is the FormatTime function code:
sub FormatTime {
##    Format Time Function    ##
##        Takes Arguments:
##        $time which is the integer value returned by the time functi
+on
##        Returns:
##        a formatted time date string

    my $time = shift;
    (my $sec, my $min, my $hour, my $mday, my $mon, my $year, my $wday
+, my $yday, my $isdst) = localtime($time);
    my $show_min = ":";
    $show_min = ":0" if $min<10;
    $mon++;
    $year += 1900;
    return "$hour$show_min$min $mon/$mday/$year";
}

[download]

At first I had shrunk that function down to almost nothing and then thought of the print command.
Instead of printing inside the loop, I repeatedly appended the output to a string $output and then printed that string outside the loop:
my $output = "";
            foreach $project_module_list (@project_module_list) {
                if($moduleCount != 0) {
                    @moduleData = split /,/, $project_module_list;
                    $output = $output . "<tr><td align=center><div cla
+ss=table_data>$moduleCount</div></td>";
                    $dataCount = 0;
                    foreach $moduleData (@moduleData) {
                        @moduleField = split /:/, $moduleData;
                        $recentChange = "";
                        $_ = $headers[$dataCount];
                        $localtime = FormatTime($moduleField[2]) if $m
+oduleField[2];
                        $localtime = "n/a" unless $moduleField[2];
                        if( /approv/i ) {
                            $status = "N/A";
                            if($moduleField[0]) {
                                $default = "checked";
                                $status = "$moduleField[1]";
                                $color = " bgcolor=\"#CCFF99\"";
                            }
                            else {
                                $default = "";
                                $color = " bgcolor=\"#FFCC66\"";
                            }
                            if($moduleField[2] > time - $changeBuffer)
+ {
                                $recentChange = " bgcolor=\"#99CCFF\""
+;
                            }
                            $output = $output . "<td$color align=cente
+r><div class=table_data><input type=checkbox name=\"$headers[$dataCou
+nt]$moduleCount\" $default></div></td><td$recentChange title=\"Change
+d by $moduleField[1] at $localtime\"><div class=table_data>$status</d
+iv></td>";
                        }
                        else {
                            if($moduleField[2] > time - $changeBuffer)
+ {
                                $recentChange = " bgcolor=\"#99CCFF\""
+;
                            }
                            $output = $output . "<td$recentChange><div
+ title=\"Changed by $moduleField[1] at $localtime\" class=table_data 
+onClick=\"ToggleShowHide('label_$headers[$dataCount]$moduleCount','$h
+eaders[$dataCount]$moduleCount')\" id=\"label_$headers[$dataCount]$mo
+duleCount\" style='display: block;'>$moduleField[0]</div> <div id=\"$
+headers[$dataCount]$moduleCount\" style='display: none;'><input type=
+text name=\"$headers[$dataCount]$moduleCount\" value=\"$moduleField[0
+]\"><input type=button onClick=\"ToggleShowHide('label_$headers[$data
+Count]$moduleCount','$headers[$dataCount]$moduleCount')\" value=OK></
+div></td>";
                        }
                        $dataCount++;
                    }
                    $output = $output . "</tr>\n";
                }
                $moduleCount++;
                $default = $color = "";
            }
            
            
            print qq~
$output
                </table>
                <script>
                    window.onload=function() { document.approve.submit
+1.disabled=false; }
                </script>
                <table border=0 cellpadding=10><tr>
                    <td>&#160;</td>
                    <td>&#160;</td>
                    <td>&#160;</td>
                    <td><input type=submit value="Save Changes" name="
+submit2"></td>
                </tr></table>
                </form>
            ~;

[download]

This changed the run time from an average of 10 seconds to 3 seconds!
To get the run time I don't do anything fancy, just print the time at the beginning and end of the script.

Thanks for all the replies!

http://uan.no-ip.org

In reply to Re^2: Foreach Loop Optimization by upallnight
in thread Foreach Loop Optimization by upallnight

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