In the API, the effect of the feature gate is that alpha fields get dropped on
create. They get preserved during updates if already set. The
PodSchedulingContext registration is *not* restricted by the feature gate.
This enables deleting stale PodSchedulingContext objects after disabling
the feature gate.
The scheduler checks the new feature gate before setting up an informer for
PodSchedulingContext objects and when deciding whether it can schedule a
pod. If any claim depends on a control plane controller, the scheduler bails
out, leading to:
Status: Pending
...
Warning FailedScheduling 73s default-scheduler 0/1 nodes are available: resourceclaim depends on disabled DRAControlPlaneController feature. no new claims to deallocate, preemption: 0/1 nodes are available: 1 Preemption is not helpful for scheduling.
The rest of the changes prepare for testing the new feature separately from
"structured parameters". The goal is to have base "dra" jobs which just enable
and test those, then "classic-dra" jobs which add DRAControlPlaneController.
The structured parameter allocation logic was written from scratch in
staging/src/k8s.io/dynamic-resource-allocation/structured where it might be
useful for out-of-tree components.
Besides the new features (amount, admin access) and API it now supports
backtracking when the initial device selection doesn't lead to a complete
allocation of all claims.
Co-authored-by: Ed Bartosh <eduard.bartosh@intel.com>
Co-authored-by: John Belamaric <jbelamaric@google.com>
This is a complete revamp of the original API. Some of the key
differences:
- refocused on structured parameters and allocating devices
- support for constraints across devices
- support for allocating "all" or a fixed amount
of similar devices in a single request
- no class for ResourceClaims, instead individual
device requests are associated with a mandatory
DeviceClass
For the sake of simplicity, optional basic types (ints, strings) where the null
value is the default are represented as values in the API types. This makes Go
code simpler because it doesn't have to check for nil (consumers) and values
can be set directly (producers). The effect is that in protobuf, these fields
always get encoded because `opt` only has an effect for pointers.
The roundtrip test data for v1.29.0 and v1.30.0 changes because of the new
"request" field. This is considered acceptable because the entire `claims`
field in the pod spec is still alpha.
The implementation is complete enough to bring up the apiserver.
Adapting other components follows.
As agreed in https://github.com/kubernetes/enhancements/pull/4709, immediate
allocation is one of those features which can be removed because it makes no
sense for structured parameters and the justification for classic DRA is weak.
This is in preparation for revamping the resource.k8s.io completely. Because
there will be no support for transitioning from v1alpha2 to v1alpha3, the
roundtrip test data for that API in 1.29 and 1.30 gets removed.
Repeating the version in the import name of the API packages is not really
required. It was done for a while to support simpler grepping for usage of
alpha APIs, but there are better ways for that now. So during this transition,
"resourceapi" gets used instead of "resourcev1alpha3" and the version gets
dropped from informer and lister imports. The advantage is that the next bump
to v1beta1 will affect fewer source code lines.
Only source code where the version really matters (like API registration)
retains the versioned import.
When a resource gets deleted during migration, the SVM SSA patch
calls are interpreted as a logical create request. Since the object
from storage is nil, the merged result is just a type meta object,
which lacks a name in the body. This fails when the API server
checks that the name from the request URL and the body are the same.
Note that a create request is something that SVM controller should
never do.
Once the UID is set on the patch, the API server will fail the
request at a slightly earlier point with an "uid mismatch" conflict
error, which the SVM controller can handle gracefully.
Setting UID by itself is not sufficient. When a resource gets
deleted and recreated, if RV is not set but UID is set, we would get
an immutable field validation error for attempting to update the
UID. To address this, we set the resource version on the SSA patch
as well. This will cause that update request to also fail with a
conflict error.
Added the create verb on all resources for SVM controller RBAC as
otherwise the API server will reject the request before it fails
with a conflict error.
The change addresses a host of other issues with the SVM controller:
1. Include failure message in SVM resource
2. Do not block forever on unsynced GC monitor
3. Do not immediately fail on GC monitor being missing, allow for
a grace period since discovery may be out of sync
4. Set higher QPS and burst to handle large migrations
Test changes:
1. Clean up CRD webhook convertor logs
2. Allow SVM tests to be run multiple times to make finding flakes easier
3. Create and delete CRs during CRD test to force out any flakes
4. Add a stress test with multiple parallel migrations
5. Enable RBAC on KAS
6. Run KCM directly to exercise wiring and RBAC
7. Better logs during CRD migration
8. Scan audit logs to confirm SVM controller never creates
Signed-off-by: Monis Khan <mok@microsoft.com>
2e34e187c9 enabled kubelet to do List and Watch
requests with the caveat that kubelet should better use a field selector (which
it does). The same is now also needed for DeleteCollection because kubelet will
use that to clean up in one operation instead of using multiple.
