NAME¶
rrdtune - Modify some basic properties of a Round Robin Database
SYNOPSIS¶
rrdtool tune filename [
--heartbeat|
-h ds-name:
heartbeat] [
--minimum|
-i ds-name:
min] [
--maximum|
-a ds-name:
max] [
--data-source-type|
-d ds-name:
DST] [
--data-source-rename|
-r old-name:
new-name] [
--deltapos scale-value] [
--deltaneg scale-value] [
--failure-threshold failure-threshold] [
--window-length window-length] [
--alpha adaption-parameter] [
--beta adaption-parameter] [
--gamma adaption-parameter] [
--gamma-deviation adaption-parameter] [
--smoothing-window fraction-of-season] [
--smoothing-window-deviation fraction-of-season] [
--aberrant-reset ds-name]
DESCRIPTION¶
The tune option allows you to alter some of the basic configuration values
stored in the header area of a Round Robin Database (
RRD).
One application of the
tune function is to relax the validation rules on
an
RRD. This allows to fill a new
RRD with data available in
larger intervals than what you would normally want to permit. Be very careful
with tune operations for COMPUTE data sources. Setting the
min,
max, and
heartbeat for a COMPUTE data source without changing
the data source type to a non-COMPUTE
DST WILL corrupt the data source
header in the
RRD.
A second application of the
tune function is to set or alter parameters
used by the specialized function
RRAs for aberrant behavior detection.
- filename
- The name of the RRD you want to tune.
- --heartbeat|-h ds-name:heartbeat
- modify the heartbeat of a data source. By setting
this to a high value the RRD will accept things like one value per
day.
- --minimum|-i ds-name:min
- alter the minimum value acceptable as input from the data
source. Setting min to 'U' will disable this limit.
- --maximum|-a ds-name:max
- alter the maximum value acceptable as input from the data
source. Setting max to 'U' will disable this limit.
- --data-source-type|-d ds-name:DST
- alter the type DST of a data source.
- --data-source-rename|-r old-name:new-name
- rename a data source.
- --deltapos scale-value
- Alter the deviation scaling factor for the upper bound of
the confidence band used internally to calculate violations for the
FAILURES RRA. The default value is 2. Note that this parameter is
not related to graphing confidence bounds which must be specified as a
CDEF argument to generate a graph with confidence bounds. The graph scale
factor need not to agree with the value used internally by the FAILURES
RRA.
- --deltaneg scale-value
- Alter the deviation scaling factor for the lower bound of
the confidence band used internally to calculate violations for the
FAILURES RRA. The default value is 2. As with --deltapos,
this argument is unrelated to the scale factor chosen when graphing
confidence bounds.
- --failure-threshold failure-threshold
- Alter the number of confidence bound violations that
constitute a failure for purposes of the FAILURES RRA. This must be
an integer less than or equal to the window length of the FAILURES
RRA. This restriction is not verified by the tune option, so one
can reset failure-threshold and window-length simultaneously. Setting this
option will reset the count of violations to 0.
- --window-length window-length
- Alter the number of time points in the temporal window for
determining failures. This must be an integer greater than or equal to the
window length of the FAILURES RRA and less than or equal to 28.
Setting this option will reset the count of violations to 0.
- --alpha adaption-parameter
- Alter the intercept adaptation parameter for the
Holt-Winters forecasting algorithm. This parameter must be between 0 and
1.
- --beta adaption-parameter
- Alter the slope adaptation parameter for the Holt-Winters
forecasting algorithm. This parameter must be between 0 and 1.
- --gamma adaption-parameter
- Alter the seasonal coefficient adaptation parameter for the
SEASONAL RRA. This parameter must be between 0 and 1.
- --gamma-deviation adaption-parameter
- Alter the seasonal deviation adaptation parameter for the
DEVSEASONAL RRA. This parameter must be between 0 and 1.
- --smoothing-window fraction-of-season
- Alter the size of the smoothing window for the SEASONAL
RRA. This must be between 0 and 1.
- --smoothing-window-deviation fraction-of-season
- Alter the size of the smoothing window for the DEVSEASONAL
RRA. This must be between 0 and 1.
- --aberrant-reset ds-name
- This option causes the aberrant behavior detection
algorithm to reset for the specified data source; that is, forget all it
is has learnt so far. Specifically, for the HWPREDICT or MHWPREDICT
RRA, it sets the intercept and slope coefficients to unknown. For
the SEASONAL RRA, it sets all seasonal coefficients to unknown. For
the DEVSEASONAL RRA, it sets all seasonal deviation coefficients to
unknown. For the FAILURES RRA, it erases the violation history.
Note that reset does not erase past predictions (the values of the
HWPREDICT or MHWPREDICT RRA), predicted deviations (the values of
the DEVPREDICT RRA), or failure history (the values of the FAILURES
RRA). This option will function even if not all the listed
RRAs are present.
Due to the implementation of this option, there is an indirect impact on
other data sources in the RRD. A smoothing algorithm is applied to
SEASONAL and DEVSEASONAL values on a periodic basis. During bootstrap
initialization this smoothing is deferred. For efficiency, the
implementation of smoothing is not data source specific. This means that
utilizing reset for one data source will delay running the smoothing
algorithm for all data sources in the file. This is unlikely to have
serious consequences, unless the data being collected for the non-reset
data sources is unusually volatile during the reinitialization period of
the reset data source.
Use of this tuning option is advised when the behavior of the data source
time series changes in a drastic and permanent manner.
EXAMPLE 1¶
"rrdtool tune data.rrd -h in:100000 -h out:100000 -h through:100000"
Set the minimum required heartbeat for data sources 'in', 'out' and 'through' to
10'000 seconds which is a little over one day in data.rrd. This would allow to
feed old data from MRTG-2.0 right into RRDtool without generating *UNKNOWN*
entries.
EXAMPLE 2¶
"rrdtool tune monitor.rrd --window-length 5 --failure-threshold 3"
If the FAILURES
RRA is implicitly created, the default window-length is 9
and the default failure-threshold is 7. This command now defines a failure as
3 or more violations in a temporal window of 5 time points.
AUTHOR¶
Tobias Oetiker <tobi@oetiker.ch>