Two days ago I finally did it: I asked a question on serverfault.com looking for advice on why our brand new server performs more poorly than our two older servers.
All the hardware details speak in favor of the new server:
But in reality, the older servers with the lower spec outperformed the new server by almost a factor of two! That is to say, for every 1 Request/sec processed the new server needed 4.5 % Processor time compared to 2.6 % on the old server. Here's a PerfMon screenshot of the new server:
New CPUs are really good at saving energy…
… actually so good, that they will rarely bother to hurry up until you really, really stress them out. Here's a good read by Brent Ozar on an energy serving CPU that would cause certain SQL queries to run two times slower on newer hardware than on the old one! That's exactly what's been happening to us.
Power Plan: From Balanced to High Performance
That brings us to: Power Plans. Windows Server and Client OSes come installed with several Power Plans, and it just so happened that the new server we had ordered with Windows Server 2012 R2 installed had its Power Plan set to Balanced (Recommended). Well, that might be a good choice for the server hoster as it helps keep the electricity bills down but it's absolutely not a good choice if you want your applications to perform well on that server. They will simply be a lot slower than the could be.
So, open the Power Options window by typing "Power Plan" into the start menu or Windows search and check the High Performance radio button:
After doins so on that new server, PerfMon would show this much more soothing picture:
Now, we have only 1,5% Processing Time per 1 Request/sec processed. That's an improvement of factor 3. Nice!
I've learned that I'm not that good of a sys admin, yet. I had been contemplating on the reasons of the poor performance of that new server of ours again and again, I had checked all kinds of settings inside IIS, ASP.NET, and the like. Those are the areas I work in day-to-day. Turns out, I needed to widen my horizon. Thanks to serverfault.com I did. And our server is at last performing as it should.