tree a370ca4a9096b1a8aae16ba436afc1fc5b960214
parent 82671ab25b7c9442f9af760f957f4764d6ef97a1
author Dmitri Shuralyov <dmitshur@golang.org> 1604667336 -0500
committer Dmitri Shuralyov <dmitshur@golang.org> 1604721332 +0000

dashboard: try to speed up pre-submit longtest builders

The longtest builders are currently primarily post-submit builders,
where it's okay for them to be as slow as they need to be in order
to provide additional test coverage. In this context, whether they
take 40 minutes or 50 makes little difference.

The longtest builders are also sometimes requested via SlowBots for
changes that are riskier than usual, or otherwise desire additional
coverage beyond the normal TryBots. They're also always enabled for
CLs to release branches. In such contexts, speeding up SlowBot runs
from 40 minutes to 20 or less would be appreciated and in turn help
people use longtest SlowBots more frequently.

Longtest builders are already configured to use sharded tests.
Configure them to use additional helpers to speed up test execution.
Try out 3, 5, and 9 helpers to see how much it helps before settling.

For golang/go#37439.

Change-Id: I425bc0257b7a54bb32c0eb1719fea7ba3f4fd461
Reviewed-on: https://go-review.googlesource.com/c/build/+/268037
Trust: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Alexander Rakoczy <alex@golang.org>
Reviewed-by: Carlos Amedee <carlos@golang.org>