new trunk based on current 1.2

[rrdtool.git] / doc / rrdcreate.pod

diff --git a/doc/rrdcreate.pod b/doc/rrdcreate.pod
index 3d4b8dd..27ef702 100644 (file)
--- a/doc/rrdcreate.pod
+++ b/doc/rrdcreate.pod
@@ -180,7 +180,9 @@ B<RRA:>I<AVERAGE | MIN | MAX | LAST>B<:>I<xff>B<:>I<steps>B<:>I<rows>
 
 I<xff> The xfiles factor defines what part of a consolidation interval may
 be made up from I<*UNKNOWN*> data while the consolidated value is still
-regarded as known.
+regarded as known. It is given as the ratio of allowed I<*UNKNOWN*> PDPs
+to the number of PDPs in the interval. Thus, it ranges from 0 to 1 (exclusive).
+
 
 I<steps> defines how many of these I<primary data points> are used to build
 a I<consolidated data point> which then goes into the archive.
@@ -200,7 +202,7 @@ flagging aberrant behavior in the data source time series:
 
 =item *
 
-B<RRA:>I<HWPREDICT>B<:>I<rows>B<:>I<alpha>B<:>I<beta>B<:>I<seasonal period>B<:>I<rra-num>
+B<RRA:>I<HWPREDICT>B<:>I<rows>B<:>I<alpha>B<:>I<beta>B<:>I<seasonal period>[B<:>I<rra-num>]
 
 =item *
 
@@ -378,6 +380,44 @@ sample. An extreme example of this might be a "step" of 5 minutes and a
 result in all the PDPs for that entire day period being set to the
 same average rate. I<-- Don Baarda E<lt>don.baarda@baesystems.comE<gt>>
 
+       time|
+       axis|
+ begin__|00|
+        |01|
+       u|02|----* sample1, restart "hb"-timer
+       u|03|   /
+       u|04|  /
+       u|05| /
+       u|06|/     "hbt" expired
+       u|07|
+        |08|----* sample2, restart "hb" 
+        |09|   / 
+        |10|  /
+       u|11|----* sample3, restart "hb"
+       u|12|   /
+       u|13|  /
+ step1_u|14| /
+       u|15|/     "swt" expired
+       u|16|
+        |17|----* sample4, restart "hb", create "pdp" for step1 = 
+        |18|   /  = unknown due to 10 "u" labled secs > "hb"
+        |19|  /
+        |20| /
+        |21|----* sample5, restart "hb"
+        |22|   /
+        |23|  /
+        |24|----* sample6, restart "hb"
+        |25|   /
+        |26|  /
+        |27|----* sample7, restart "hb"
+ step2__|28|   /
+        |22|  /
+        |23|----* sample8, restart "hb", create "pdp" for step1, create "cdp" 
+        |24|   /
+        |25|  /
+
+graphics by I<vladimir.lavrov@desy.de>.
+
 
 =head1 HOW TO MEASURE
 
@@ -510,4 +550,4 @@ RPN expression handles the divide by zero case.
 
 =head1 AUTHOR
 
-Tobias Oetiker E<lt>oetiker@ee.ethz.chE<gt>
+Tobias Oetiker E<lt>tobi@oetiker.chE<gt>