after fetching, data must be reduced to at least chart resolution, else some data...

[rrdtool.git] / src / rrd_graph.c

diff --git a/src/rrd_graph.c b/src/rrd_graph.c
index d7781f6..3f8ee1b 100644 (file)
--- a/src/rrd_graph.c
+++ b/src/rrd_graph.c
@@ -896,11 +896,15 @@ int data_fetch(
                                 &im->gdes[i].ds_cnt,
                                 &im->gdes[i].ds_namv,
                                 &im->gdes[i].data)) == -1) {
-                    return -1;
-                }
+                    return -1;                      
+                }               
             }
             im->gdes[i].data_first = 1;
 
+            /* must reduce to at least im->step
+               otherwhise we end up with more data than we can handle in the 
+               chart and visibility of data will be random */            
+            im->gdes[i].step = max(im->gdes[i].step,im->step);
             if (ft_step < im->gdes[i].step) {
                 reduce_data(im->gdes[i].cf_reduce,
                             ft_step,