Splunk Search

Optimizing the search

abhi04
Communicator

Hi All,

 

How can I optimize the below query? Can we convert it to tstats?

 

index=abc host=def* stalled
| rex field=_raw "symbol (?<symbol>.*) /"
| eval hourofday = strftime(_time, "%H")
| where NOT (hourofday>2 AND hourofday <= 4)
| timechart dc(symbol) span=15m
| eventstats avg("count") as avg stdev("count") as stdev
| eval lowerBound=-1, upperBound=(avg+stdev*exact(4))
| eval isOutlier=if('count' < lowerBound OR 'count' > upperBound, 1, 0)
| fields _time, "count", lowerBound, upperBound, isOutlier, *
| sort -_time
| head 1
| where isOutlier=1
Labels (1)
0 Karma
1 Solution

bowesmana
SplunkTrust
SplunkTrust

 

Use TERM(stalled), as that will help filter the initial data volume retrieved

The order of commands is important - you are doing the rex before the hour constraint - change the order.

You may already have a field called date_hour (it is often extracted by default - check). If so you can put that in the search 

index=abc host=def* stalled (date_hour < 3 OR date_hour > 4)
| rex field=_raw "symbol (?<symbol>.*) /"
| timechart dc(symbol) span=15m

Replace the NOT with a positive constraint, i.e. check that the hour is < 3 or > 4 rather than NOT >2 AND <4

You can't convert it to tstats unless symbol becomes an indexed field.

 

View solution in original post

abhi04
Communicator

This is awesome, thanks @bowesmana . And, yes, it was a type for the "count" 🙂

0 Karma

bowesmana
SplunkTrust
SplunkTrust

and there is a basic problem with that search anyway, which is that you are using a field called "count", which does not exist - your timechart will produce a field called dc(symbol). I assume that is a typo and that your real search does dc(symbol) as count

 

0 Karma

bowesmana
SplunkTrust
SplunkTrust

 

Use TERM(stalled), as that will help filter the initial data volume retrieved

The order of commands is important - you are doing the rex before the hour constraint - change the order.

You may already have a field called date_hour (it is often extracted by default - check). If so you can put that in the search 

index=abc host=def* stalled (date_hour < 3 OR date_hour > 4)
| rex field=_raw "symbol (?<symbol>.*) /"
| timechart dc(symbol) span=15m

Replace the NOT with a positive constraint, i.e. check that the hour is < 3 or > 4 rather than NOT >2 AND <4

You can't convert it to tstats unless symbol becomes an indexed field.

 

Get Updates on the Splunk Community!

Splunk Search APIを使えば調査過程が残せます

   このゲストブログは、JCOM株式会社の情報セキュリティ本部・専任部長である渡辺慎太郎氏によって執筆されました。 Note: This article is published in both Japanese ...

Integrating Splunk Search API and Quarto to Create Reproducible Investigation ...

 Splunk is More Than Just the Web Console For Digital Forensics and Incident Response (DFIR) practitioners, ...

Congratulations to the 2025-2026 SplunkTrust!

Hello, Splunk Community! We are beyond thrilled to announce our newest group of SplunkTrust members!  The ...