Previously, the build ID would never flow through channels which
exited.
This patch tracks the buildOne state as part of State and exits avoids
waiting forever for new work.
The code around buildOnly is a bit rough, making this a bit weird to
implement but since it is only used for testing the value of improving
it on its own is a bit questionable.
If we don't see machine that supports a build step for
'max_unsupported_time' seconds, the step is aborted. The default is 0,
which is appropriate for Hydra installations that don't provision
missing machines dynamically.
(cherry picked from commit f5cdbfe21d)
Same problem as d744362e4a.
at /nix/store/ksvsbr7pg4z69bv6fbbc8h7x7rm2104m-gcc-4.9.3/include/c++/4.9.3/bits/predefined_ops.h:166
__last@entry=..., __comp=...) at /nix/store/ksvsbr7pg4z69bv6fbbc8h7x7rm2104m-gcc-4.9.3/include/c++/4.9.3/bits/stl_algo.h:1827
__comp=...) at /nix/store/ksvsbr7pg4z69bv6fbbc8h7x7rm2104m-gcc-4.9.3/include/c++/4.9.3/bits/stl_algo.h:4717
For example, steps that require the "kvm" feature may require a
different kind of machine to be provisioned. This can also be used to
require performance-sensitive tests to run on a particular kind of
machine, e.g., by setting requiredSystemFeatures to something like
"ec2-i2.8xlarge".
"hydra-queue-runner --status" now prints how many runnable and running
build steps exist for each machine type. This allows additional
machines to be provisioned based on the Hydra load.
