In the past, jobsets which are automatically evaluated are evaluated
regularly, on a schedule. This schedule means a new evaluation is
created every checkInterval seconds (assuming something changed.)
This model works well for architectures where our build farm can
easily keep up with demand.
This commit adds a new type of evaluation, called ONE_AT_A_TIME, which
only schedules a new evaluation if the previous evaluation of the
jobset has no unfinished builds.
This model of evaluation lets us have 'low-tier' architectures.
For example, we could now have a jobset for ARMv7l builds, where
the buildfarm only has a single, underpowered ARMv7l builder.
Configuring that jobset as ONE_AT_A_TIME will create an evaluation
and then won't schedule another evaluation until every job of
the existing evaluation is complete.
This way, the cache will have a complete collection of pre-built
software for some commits, but the underpowered architecture will
never become backlogged in ancient revisions.
This attribute allows to know if an error occurred or not: when an
error occurs, errormsg is not an empty string. Note we can not use the
errormsg attribute because it can be arbitrarily long and is excluded
from the jobset API response.
This adds the following (pre-existing) attributes to the jobset response:
- nrtotal
- lastcheckedtime
- starttime
- checkinterval
- triggertime
- fetcherrormsg
- errortime
Currently, a full store path has to be provided to search in
builds. This patch permits to search jobs with a output path or
derivation hash.
Usecase: we are building Docker images with Hydra. The tag of the
Docker image is the hash of the image output path. This patch would
allow us to find back the build job from the tag of a running
container image.
This is a good way to make Hydra hang. (E.g. we had a deletion of
nixos:gcc-7 running for > 12 hours and blocking UPDATE statements from
hydra-queue-runner.) Generally it's better to just disable/hide an old
jobset anyway.
Frequently users want Hydra access just to restart jobs. However,
prior to this commit the only way to grant that access was by giving
them full Admin access which isn't necessarily what we want to do.
By having a restart-jobs role, we can grant this privilege to users
who are known to the community and want to help, but aren't long-time
members.
I haven't tested this commit, but it looks good to me...
This makes downloading/viewing build results work with binary cache
stores. For good performance, this should be used in conjunction with
ca580bec35,
i.e. you should set store_uri to something like
s3://my-cache?local-nar-cache=/tmp/nar-cache
to cache NARs between requests.
