Knowledge Management

## Using mean(x) in summary search run every 5 minutes - when running a report on summary index using mean(x) per day or month, will that give the same result?

Communicator

Hi - I need to calculate the mean(response time) for at complete month based on summary index.

The summary index search has to run every 5 minutes - selecting last 5 minutes of data.

The search will look like this: Search.... |sistats mean(response time) by xxx yyyy www ttt

The monthly report search will look like this: index=summary REPORT=MEANRESP|timechart span=1month mean(response time)

QUESTION: Will the search run on the summary index give the same result as if I made the search run on the actual transaction log?

Tags (2)
1 Solution
Revered Legend

There will be some differences (magnitude depend upon the data) as there will be little rounding in mean calculation of summary indexes and subsequent mean calculation during data fetch from. See this runanywhere search example and compare the results.

``````SET 1
simulating summary index
| gentimes start=-1 | eval temp=mvrange(1,200,2) | table temp | mvexpand temp | eval data=temp+1 | bucket span=5s data | stats mean(temp) as temp by data | stats mean(temp) as temp

Direct calculation
| gentimes start=-1 | eval temp=mvrange(1,200,2) | table temp | mvexpand temp | eval data=temp+1 | stats mean(data) as temp

SET 2
simulating summary index
| gentimes start=-1 | eval temp=mvrange(2,200,2) | table temp | mvexpand temp | eval data=temp+1 | bucket span=5s data | stats mean(temp) as temp by data | stats mean(temp) as temp

Direct calculation
| gentimes start=-1 | eval temp=mvrange(2,200,2) | table temp | mvexpand temp | eval data=temp+1 | stats mean(data) as temp
``````
Revered Legend

There will be some differences (magnitude depend upon the data) as there will be little rounding in mean calculation of summary indexes and subsequent mean calculation during data fetch from. See this runanywhere search example and compare the results.

``````SET 1
simulating summary index
| gentimes start=-1 | eval temp=mvrange(1,200,2) | table temp | mvexpand temp | eval data=temp+1 | bucket span=5s data | stats mean(temp) as temp by data | stats mean(temp) as temp

Direct calculation
| gentimes start=-1 | eval temp=mvrange(1,200,2) | table temp | mvexpand temp | eval data=temp+1 | stats mean(data) as temp

SET 2
simulating summary index
| gentimes start=-1 | eval temp=mvrange(2,200,2) | table temp | mvexpand temp | eval data=temp+1 | bucket span=5s data | stats mean(temp) as temp by data | stats mean(temp) as temp

Direct calculation
| gentimes start=-1 | eval temp=mvrange(2,200,2) | table temp | mvexpand temp | eval data=temp+1 | stats mean(data) as temp
``````
Get Updates on the Splunk Community!

#### Splunk Education - Fast Start Program!

Welcome to Splunk Education! Splunk training programs are designed to enable you to get started quickly and ...

#### Five Subtly Different Ways of Adding Manual Instrumentation in Java

You can find the code of this example on GitHub here. Please feel free to star the repository to keep in ...

#### New Splunk APM Enhancements Help Troubleshoot Your MySQL and NoSQL Databases Faster

Splunk Observability has two new enhancements to make it quicker and easier to troubleshoot slow or frequently ...