Linux benchmarks are included here: https://github.com/aspnet/benchmarks/
The team definitely wants to make ASP.NET Core run fast on Linux, too. The ASP.NET team perf rig runs both Ubuntu 14.04 LTS and Windows Server 2012 R2. A lot of the perf enhancements are due to community pull requests, mostly from Ben (author of parent post). The perf work's been discussed a lot on the weekly community standup calls (http://live.asp.net), here's one going over the rig and perf in general: https://www.youtube.com/watch?v=7O81CAjmOXk&list=PL0M0zPgJ3H...
There's a lot going on right now - both ASP.NET Core and .NET Core are new to Linux, the teams are working on getting 1.0 releases out the door, etc. I expect perf on both Windows and Linux to continue to improve, both before and after 1.0 release. This week on the community standup, Damian said that perf is one area that's lower risk as RTM approaches, and that they're hoping for more improvement there.
And this is very much an open source project, as you can see from the merged pull requests in general (https://github.com/aspnet/KestrelHttpServer/pulls?q=is%3Apr+...) and the fact that Ben (non m-dollar) is battling with a Microsoft dev to be the top contributor. It'd be great to get some more devs with Linux HTTP serving background contributing.
I think I remember that they only posted benchmark updates when there was a significant change. Checking with the team now.
Source: long time ASP.NET groupie, Microsoft employee (until they find out I'm goofing off on HN instead of replying to e-mail).
Last month, I did some Linux profiling in our perf lab. As part of that, I ran the exact same benchmark shown in that graph on the exact same equipment and got over double the RPS numbers we got back in November much like we did on Windows.
I just updated the https://github.com/aspnet/benchmarks/ repo with the linux numbers I got last month since Ben's blog post has brought some increased attention to it. We plan to do a more complete benchmark run soon so we can update more numbers.