This adds a counter to the scheduler that can be used to calculate
throughput and error ratio. Pods which fail to schedule are not counted
as errors, but can still be tracked separately from successes.
We already measure scheduler latency, but throughput was missing. This
should be considered a key metric for the scheduler.
This adds counters to equiv. cache reads & writes. Reads are labeled by
hit/miss, while writes are labeled to indicate whether the write was
discarded.
This will give us visibility into,
- hit rate of cache reads
- ratio of reads to writes
- rate of discarded writes
This moves plugin/pkg/scheduler to pkg/scheduler and
plugin/cmd/kube-scheduler to cmd/kube-scheduler.
Bulk of the work was done with gomvpkg, except for kube-scheduler main
package.
