x/build: restore performance benchmarking dashboard

[ianlancetaylor]

In a trybot run in https://storage.googleapis.com/go-build-log/dd2f2f0c/linux-amd64_19b3a9d1.log , after the build and the tests are complete, I see this:

##### 
iteration: 0
start-time: 2017-06-02T00:53:45Z
building testgo failed: exit status 1
can't load package: package .: no buildable Go source files in /tmp/workdir/go-parent

Error: tests failed: dist test failed: bench:bench-cmd-go.exe -test.bench . -test.benchmem -test.run ^$ -test.benchtime 100ms: exit status 2

[ianlancetaylor]

Another trybot run: https://storage.googleapis.com/go-build-log/f7eb06b6/linux-amd64_26eecad0.log

[bradfitz]

@quentinmit, this looks like the new benchmarks-on-trybot code having problems in some cases. Can you take a look?

[bradfitz]

Another:
https://storage.googleapis.com/go-build-log/12c54536/linux-amd64_c57e3046.log
From:
https://go-review.googlesource.com/c/46030/

@quentinmit ?

[bradfitz]

"use of internal package not allowed"
https://storage.googleapis.com/go-build-log/8a70806e/linux-amd64_ca9bc8f3.log

[bradfitz]

Trybot benchmarking was disabled, as announced on golang-dev, so pushing this to Go 1.10.

[ysmolski]

Part of the problem is that I cannot not figure out how to run trybots, etc builder services locally to tinker with it and being able to see results. In case of Playground I could run the whole thing in a docker.

@bradfitz, How does contributors to x/build run trybots locally?

[bradfitz]

@ysmolsky, unfortunately the build system is not easy to hack on locally. It's possible, but pretty tedious and you need to be pretty aware of how it all works. Often times we do most of our testing in our dev+staging GCP project.