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Arslan11's avatar
Arslan11
Brass Contributor
Apr 30, 2020

Report on selected servers for a week on the memory usage

I would like a help with a Kusto  query which I have almost completed but I am struggling in the last part.   Kusto query Perf | where ObjectName == "Memory" and CounterName == "% Committed Bytes...
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SamsonJohn's avatar
SamsonJohn
Copper Contributor
May 04, 2020

CliveWatson 

 

Hello Clive  thanks for the query , but what I observe is the difference in the actual memory in the Virtual Machine when compared with query output.

I used this query

Perf
| where TimeGenerated > startofday(ago(5d))
| where ObjectName == "Memory" and CounterName == "% Committed Bytes In Use"
| extend Used_Percent_Memory = 100- CounterValue
| summarize Used_Percent_Memory = max(CounterValue)by bin(TimeGenerated,1d) , Computer, ObjectName
| where Used_Percent_Memory < 90 and Used_Percent_Memory > 70

 

So when a login to VM if I check , the latest it show memory less than 80 for live0 and live1  and for DB it is 87 % memory utilized

 

Please refer the above graph , not sure why this difference is coming

 
 

 

 

 

CliveWatson's avatar
CliveWatson
Former Employee
May 04, 2020

SamsonJohn 

 

In this section of the query we look at memory between 70 & 90 %, we take the max value seen on a given day (the BIN takes all the daily values and gives us one figure)

 

| summarize Used_Percent_Memory = max(CounterValue)by bin(TimeGenerated,1d) , Computer, ObjectName
| where Used_Percent_Memory < 90 and Used_Percent_Memory > 70

 

So when a login to VM if I check , the latest it show memory less than 80 for live0 and live1  and for DB it is 87 % memory utilized

 

So if memory is above 70% you will see it, based on the max value for that day, which isn't necessarily the current value.

 

You may need to look at the past hour broken into 1m BINS for this?

 

Perf
| where TimeGenerated > ago(1h)
| where ObjectName == "Memory" and CounterName == "% Committed Bytes In Use"
| extend Used_Percent_Memory = 100- CounterValue
| summarize Used_Percent_Memory = max(CounterValue) by bin(TimeGenerated,1m) , Computer, ObjectName
//| where Used_Percent_Memory < 90 and Used_Percent_Memory > 70
| render timechart

 

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