In SharePoint 2013, I am creating a new Subsite, and after 2 minutes my browser (IE 10), gives me a message of " Connection Time Out" in 60 ms. But when I again look in the list of Subsites, my new subsite is created. Its strange that the browser gives me this message, but however makes a new subsite.

I did below steps for investigation:

1 - Ran SQL Profiler, as I thought there is a time out from there. But it wasnt from there

2 - Ran Developer Dashboard (I can run it but there is no data coming there - another issue)

3 - The limit in the IIS Sites are 120 seconds in the Advanced Settings option, and I am receiving the time out message in 61 s . Used F12 developer tools

My SharePoint 2013 has 3 Site Collections and Total Content DB will be around 900GB.

2 App Server, 2 front Ends, 1 Database Server and SQL is running on a separate instance.

Any suggestions please