For AWS EBS, a volume can only be attached to a node in the same AZ.
The scheduler must therefore detect if a volume is being attached to a
pod, and ensure that the pod is scheduled on a node in the same AZ as
the volume.
So that the scheduler need not query the cloud provider every time, and
to support decoupled operation (e.g. bare metal) we tag the volume with
our placement labels. This is done automatically by means of an
admission controller on AWS when a PersistentVolume is created backed by
an EBS volume.
Support for tagging GCE PVs will follow.
Pods that specify a volume directly (i.e. without using a
PersistentVolumeClaim) will not currently be scheduled correctly (i.e.
they will be scheduled without zone-awareness).
1. Name default scheduler with name `kube-scheduler`
2. The default scheduler only schedules the pods meeting the following condition:
- the pod has no annotation "scheduler.alpha.kubernetes.io/name: <scheduler-name>"
- the pod has annotation "scheduler.alpha.kubernetes.io/name: kube-scheduler"
update gofmt
update according to @david's review
run hack/test-integration.sh, hack/test-go.sh and local e2e.test
To improve the throughput of current scheduler, we can do
a simple optimization by calcluating priorities in parallel.
This doubles the throughput of density test, which has the default
config with 3 priority funcs (the spreading one does not actually
consume any computation time). It matches the expectation.
The "Combined requested resources" message becomes excessive as
the cluster fills up, drop it down to V(2)
Put an explicit V(2) on the only other scheduler Infof call that didn't
have V specified already.
Set the out of disk node condition to unknown in the node controller if
the kubelet does not report its node condition in a long time. Update
node controller unit tests.
Implement a node condition predicate function that checks if a given
node satisfies the conditions defined by the predicate and if it
does, use that node for scheduling pods. The predicate function takes
both NodeReady and NodeOutOfDisk into consideration to determine if a
node is fit for scheduling pods.
The predicate is then passed to the node lister in the scheduler factory
so that the node lister can run the predicate function on the nodes when
schedling pods thereby omitting nodes that does not satisfy the
predicate.
Also update listers test.
