Historical Data Calculation of Calculator outputs

[Geethu John]

Hi all ,

 

Has anyone faced discrepancies in values/outputs of calculators, when historical view is taken and  resolution is increased?

Suppose I have a metric in Investigator :

 

Say MethodA - The ART values for 8 data points are 0,0,0,3044,0,0,3132,2942.

I created a simple sum calculator out of this which will in turn give me the same value.

I created a java-script calculator to average the response time of MethodA and MethodB which will have a different data set. Suppose MethodB ART is always zero , then java script calculator should be giving me the same output as MethodA ART.

 

So I have three graphs now. MethodA , Simple Calculator and Javascript Calculator.

 

If I click on historical view and set the resolution as 1 minute , the above 8 data points will be averaged to 2 points. But the values of those 2 data points in the all the three graphs are different.

(According to me, it should be giving me the same output).

 

Method A gives - 3044 and 3037 -------> (3044/1 and (3132+2942)/2). Here , only those data points > 0 are considered for average calculation , which makes sense.

 

Simple Calculator - 3044 and 3132 ( Here it considers the data point which has the maximum value )

 

Java script calculator - 761 and 1519 ( Here it just takes all the points and divide by 4. (0+0+0+3444)/4 and (0+0+3132+2942)/4.

 

 

 

 

Am I missing anything ? Or this is how calculators behave when historical values are taken?

 

Thanks

Geethu

[Hallett German]

Hi Geethu:

       What version are running and can you attach the Javascript calculator?

    Thanks

Hal German

[Geethu John]

Hi Hal,

 

I am running 9.5.2..

 

Attaching the script :

Attachment(s)

OperationART.txt.zip   1 KB 1 version

[Matthew Muskaloon]

Hi Geethu,

 

We need some more information. 

 

1. What type of calculator are you using?  Sum, Average, Min or Max?

2. What is your time frame that you are comparing.  You have the resolution at 1 minute, but what is your time range?

 

Smartstor tiering can affect this if your time range goes beyond the first tier.

 

Matt

[Thomas Wyszomierski]

It would also be interesting to know if you are using a Counter or Interval Counter for your calculator. Interval Counters will sum values aggregated over time while a counter will return the highest value over the interval. For older metrics, smartstor tiers can also create inconsistencies between metrics and calculators derived by those metrics.

[Geethu John]

Hi Thomas,

 

I use counter for my calculators as the input was response times. I tried interval counter,but as you said , it just sums up everything in that interval.

 

Just wondering , how the metrics in Investigator tree show up everything so beautifully when we take different averages.

Is it a different logic or algorithm that gets applied when we create calculators?

 

Geethu

[Hallett German]

Geethu:

In talking with Matt, the best course of action would be open a case to resolve.

 

Thanks

Hal German

[Geethu John]

Hi Matt,

 

The simple Introscope calculator that I use is sum operation. Because I need the sum of response times of few processes

 

I take the sum of say 5 processes from server 1 and similarly take the sum of similar 5 processes from server 2. So I use two simple calculators here.Then I use a JS calculator to take the average so that it will not count datapoints with 0 value for average calculation.

 

Also , the time frame is 8 minutes only.

 

Geethu