I was troubleshooting performance issues today and needed to analyze IIS logs to see which requests are slow. In the past I was able to use just Notepad to do that for small logs. Today’s log was 172 MB in size, and I had some serious issues, even with Notepad++ trying to make sense of the data. I looked around and found this great tool: Log Parser Studio.
You can download it from Tech Net Marketplace: https://gallery.technet.microsoft.com/Log-Parser-Studio-cd458765.
Once you donwload and unzip it, you will get a prompt to download LogParser. Go ahead and do that. Once you restart the studio, you will be able to query your data using T-SQL like language. Click open folder yellow button and add your log files first. Then you can use Search box to browse pre-built queries that ship with the tool, such as TOP 25 Slowest Url requests.
If you look at the query window, you will see the following:
SELECT TOP 25
cs-uri-stem as URL,
MAX(time-taken) As Max,
MIN(time-taken) As Min,
Avg(time-taken) As Average
GROUP BY URL
ORDER By Average DESC
Now you can open a new query and start playing with your own data. Executing top 25 slow URLs on my machine tool 1 second – that is on 172 MB worth of IIS logs.
I love this tool from Microsoft!