Builds can now emit metrics that Hydra will store in its database and
render as time series via flot charts. Typical applications are to
keep track of performance indicators, coverage percentages, artifact
sizes, and so on.
For example, a coverage build can emit the coverage percentage as
follows:
echo "lineCoverage $pct %" > $out/nix-support/hydra-metrics
Graphs of all metrics for a job can be seen at
http://.../job/<project>/<jobset>/<job>#tabs-charts
Specific metrics are also visible at
http://.../job/<project>/<jobset>/<job>/metric/<metric>
The latter URL also allows getting the data in JSON format (e.g. via
"curl -H 'Accept: application/json'").
Without an index on (machine, stoptime desc), this requires a
sequential scan. And adding a whole index for this seems
overkill. (Possibly the queue runner could maintain this info more
efficiently.)
Hydra-queue-runner now no longer polls the queue periodically, but
instead sleeps until it receives a notification from PostgreSQL about
a change to the queue (build added, build cancelled or build
restarted).
Also, for the "build added" case, we now only check for builds with an
ID greater than the previous greatest ID. This is much more efficient
if the queue is large.
This removes the need for Nix's build-remote.pl.
Build logs are now written to $HYDRA_DATA/build-logs because
hydra-queue-runner doesn't have write permission to /nix/var/log.
Scheduling is mostly based on jobset shares these days. So showing and
sorting by priority just wastes space and gives the incorrect
impression that Hydra executes builds in the order shown on the queue
page.
These give warnings in Perl >= 5.18:
given is experimental at /home/hydra/src/hydra/src/lib/Hydra/Helper/CatalystUtils.pm line 241.
when is experimental at /home/hydra/src/hydra/src/lib/Hydra/Helper/CatalystUtils.pm line 242.
...