I have a Web App that runs on a Windows Server 2008 Standard running in VMWare ESXi. It has 8GB of RAM and 4 virtual processors. I am using the Abyss Webserver and the app is accessed securely (HTTPS). The database is MS-SQL Server 2008. I have had intermittent problems since it has been deployed. I added a second Web App and today it began to get some use and it started having problems. The app was sluggish and would simply drop off line from time to time. It is so problematical it cannot really be used.
It was built with 2014r3.1 but I also tried 2014r2.1 with the same results.
As I dug into things with Resource Monitor (which can be run from the Performance Tab of the Task Manager in Server) I saw many TCP Connections listed as “IPv4 loopback”. If the app is not being accessed (no active browser connections) the TCP connections drops to just a few and none are loopback. When the first connection comes up to the login page the app spikes to at least 50 TCP connections that are mostly these “IPv4 loopback”. These show in the resource monitor with no Image Name (program) and no PID (Process ID). The local port is listed as a high number port (50,000 range) and all seem to increment by one for each. The remote port is the same for every one of these TCP loopback connections generally in the 25,000 range.
If I launch the login page and do nothing it seems to create about 50 connections and more than 40 are these loopback connections. If I type the User ID and tab to the password field the TCP connections spikes to more than 100 then in a minute or so starts to settle back to the 50 level. I do have a keypress event that looks for the ENTER key for the UserID and PW (the only keypress events in the app).
If I go ahead and login to the first main page and do nothing I can see the connections spike to well over 250 and slowly rise to maybe 300 even if I do nothing. This is all with no other users in the system. If I logout and close the browser it settles back to only a few connections and no loopback connections. If I remain on a page in the app the loopback connections start to drop. I have a 15 minute timeout and by the time that is reached there are about 25 connections.
I have another totally different virtual server in a different datacenter that is a very similar configuration except it uses MySQL. It does seem to spike some loopback processes but not so many and the app generally works very well. The app on this server is much more complex.
Is this normal behavior?
Where else should I look?