The Performance Tuning Guidelines for Windows Server 2012 is available for download as of July 24, 2012 and I would like to recommend the lectures to any system administrator with above the average devotion. The currently 150 pages long document includes topics for storage, networking and hardware/power, but also shines with server role based chapters such as web, file, AD, RD and much more services even including SAP.
Enough adds, here my first impressions:
The content gets interesting already on page 20 with the networking subsystem architecture, understandable explanations of the many optimization features such as offload capabilities (checksum, RSC, RSS, etc.) and on page 26 the reader is rewarded with an overview grid of different services and relevant optimizations therefore. On page 29 I was positively surprised to see an explicit listing of registry features, that are not supported anymore, and these are:
Finally I won’t miss the TcpWindowSize anymore, as was the case in earlier versions: although Server 2008 and 2008 R2 were TCP Receive Window Auto-Tuning-aware, I was having troubles fully utilizing a single (or even more) 1GB Ethernet connection. Iperf test then showed as low as 82% utilization and only adjusting manually to higher Window Sizes. Obviously Microsoft succeeded by the improvement of the network subsystem, because my recent Server 2012 iperf-test ran with satisfactory 112-113MByte/s without any optimization or manual adjustments.
Out of the box there comes also the Ntttcp – ttcp port for windows with which you can check the network throughput. A couple of examples are included on page 32.
I must admit that Srv2012 improved its overall network subsystem not only on terms of performance but also rich featured, such as teaming for different NIC vendors, etc. thus making the current platform a reliably stronghold for any kind of applications.