I am thinking of buying Dell server with E5 CPU and either X520 NIC or Solaflare 5122.
If I buy X520 - Is there a tool or API to collect credible latency information on Windows without expensive setup involving 2 servers with 10GBe cards and a 10GBe switch.
If there is no tool perhaps there is some API Intel NIC exposes.
I can write a custom app on .NET to measure down to 1 microsecond (jitter will be large but I need somewhere to start).
Have you considered Netperf? I know many of Solarflare's customers are using that. You should be able to test server to server with a standard twinax DAC between cards. As for the SFN5122F that is one of our lowest latency cards, however the kernal bypass middleware (OpenOnload) for that currently will only run in a linux environment. For Windows I would suggest one of our performant level cards such as the SFN5162F,which also has very good latency.