Are all_max_peak percentile calculations wrong?

Hello,

as far as I checked and understood the source code the
calculations for 'all_max_peak' are wrong currently.

For type 'max' as well as 'all_max_peak' function 
nth_percentile() is called with one $local_data_id,
returning a nth_percentile for the given datasource as
well as a calculated field 'nth_percentile_maximum'.

When using 'max', this field 'nth_percentile_maximum' is
used and this looks right for me.

When using 'all_max_peak', the nth_cache is iterated, seeking
for a maximum. But within each iteration the nth_percentile_maximum
is used which should be the same for every local_data_id of that 
RRD. I think the iteration should seek for the maximum of the
n'th percentiles of the respective data sources.


The following patch makes that happen:

root@cacti:/var/www/cacti_test# diff -u lib/graph_variables.php.20121008-dist  lib/graph_variables.php
--- lib/graph_variables.php.20121008-dist	2012-10-25 15:18:56.000000000 +0200
+++ lib/graph_variables.php	2012-10-25 15:58:42.000000000 +0200
@@ -366,8 +366,8 @@
 	}elseif ($regexp_match_array[4] == "all_max_peak") {
 		for ($t=0;($t<count($graph_items));$t++) {
 			if ((preg_match("/(AREA|STACK|LINE[123])/", $graph_item_types{$graph_items[$t]["graph_type_id"]})) && (!empty($graph_items[$t]["data_template_rrd_id"]))) {
-				if (! empty($nth_cache{$graph_items[$t]["local_data_id"]}["nth_percentile_maximum"])) {
-					$local_nth = $nth_cache{$graph_items[$t]["local_data_id"]}["nth_percentile_maximum"];
+				if (! empty($nth_cache{$graph_items[$t]["local_data_id"]}{$graph_items[$t]["data_source_name"]})) {
+					$local_nth = $nth_cache{$graph_items[$t]["local_data_id"]}{$graph_items[$t]["data_source_name"]};
 					$local_nth = ($regexp_match_array[2] == "bits") ? $local_nth * 8 : $local_nth;
 					$local_nth /= pow(10,intval($regexp_match_array[3]));


Is anyone able and willing to comment on this, check 
my investigations or correct me?


Regards
Florian



-- 
  Florian Roscher                          private: [email protected]
                                            Debian: [email protected] 
PGP Key / ID: 1024D/B4071A65
Fingerprint : F9AB 00C1 3E3A 8125 DD3F  DF1C DF79 A374 B407 1A65

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