What is the purpose of Calculate Trend Size and Calculate Trend Status in KPI Manager?

Answer

There are 3 attributes that together help determine the trend for the KPI values.

These attributes are:

TRENDENABLED - Y/N: determines whether trend calculation is enabled. Trends are calculated when a KPI value is saved. Enabling this attribute would slow down that process, so is disabled by default.

TRENDBATCHSIZE - determines the batch size of KPI values that it includes - default is 100.

TRENDVALUE- this value is calculated by using the least squares regression model (the Apache commons math implementation) over the configured batch size of KPI values. You can change the algorithm by implementing your own. All you need to do is extend the com.ibm.tivoli.maximo.trend.BaseTrendProvider and implementing the following method:

public double getKPITrend(String kpiname, int batchSize) throws MXException

You need to register the custom class with the property mxe.default.trendprovider.

The default implementation is provided by the com.ibm.tivoli.maximo.trend.DefaultTrendProvider (least squares regression model).

As a general guideline, if the trend value is negative, it implies a downward trend and a positive value indicates otherwise. A value close to 0 would indicate more of a horizontal trend.