Use single query to fetch commit runs and metric runs (instead of individual selects).
Hopefully this enables some kind of prefetching.
But more importantly it allows to work around "gaps" in commit nums,
as we only fetch data that is actually in the database
and don't try to query all commit runs in the "gap".
LGTM=adg
R=adg
CC=golang-codereviews, rsc
https://golang.org/cl/159910045
Currently we still see some flakes on perf dashboard (e.g. sys-stack is quite frequent).
I am planning to run real perf builder with 5 different values of GOMAXPROCS,
so we can require 3 builders to agree on a change instead of 2.
This will provide 20x improvement in flake detection.
At the same time lower noise bar from 1.2 to 1.1, as I see some real perf changes gets ignored as noise.
All these magic numbers affect only representation of data, but not the data stored in DB.
So we can continue freely tuning them later. There are no significant risks here.
LGTM=adg
R=adg
CC=golang-codereviews
https://golang.org/cl/127520044
This CL moves code from code.google.com/p/dvyukov-go-perf-dashboard,
which was previously reviewed.
LGTM=adg
R=adg
CC=golang-codereviews
https://golang.org/cl/96180043