Skip to content

fix: skip not-ready sandboxes during warm pool adoption #519

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
noeljackson wants to merge 1 commit into
base: main
Choose a base branch
from
+85 −4
Open

fix: skip not-ready sandboxes during warm pool adoption #519

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 6 additions & 0 deletions extensions/controllers/sandboxclaim_controller.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -415,6 +415,12 @@ func (r *SandboxClaimReconciler) adoptSandboxFromCandidates(ctx context.Context,
currIndex := (startIndex + i) % n
adopted := candidates[currIndex]

if !isSandboxReady(adopted) {
Copy link
Copy Markdown
Contributor

@justinsb justinsb Apr 3, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This seems reasonable, but if there is no ready sandbox, do we want to fall-back to a non-ready Sandbox? I'm imagining the (pathological) case that a Sandbox takes 2 minutes to start up; is it better to use a Sandbox that is 1 minute into startup in that case?

logger.V(1).Info("skipping not-ready adoption candidate",
"sandbox", adopted.Name, "claim", claim.Name)
continue
}

// Extract pool name from owner reference before clearing
poolName := "none"
if controllerRef := metav1.GetControllerOf(adopted); controllerRef != nil {
Expand Down
83 changes: 79 additions & 4 deletions extensions/controllers/sandboxclaim_controller_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,7 @@ import (

"github.com/google/go-cmp/cmp"
"github.com/prometheus/client_golang/prometheus/testutil"
"github.com/stretchr/testify/require"
corev1 "k8s.io/api/core/v1"
networkingv1 "k8s.io/api/networking/v1"
k8errors "k8s.io/apimachinery/pkg/api/errors"
Expand Down Expand Up @@ -934,16 +935,15 @@ func TestSandboxClaimSandboxAdoption(t *testing.T) {
expectNewSandboxCreated: false,
},
{
name: "adopts oldest non-ready sandbox when no ready sandboxes exist",
name: "skips not-ready sandboxes and falls through to cold creation",
existingObjects: []client.Object{
template,
claim,
createWarmPoolSandbox("not-ready-1", metav1.Time{Time: metav1.Now().Add(-2 * time.Hour)}, false),
createWarmPoolSandbox("not-ready-2", metav1.Time{Time: metav1.Now().Add(-1 * time.Hour)}, false),
},
expectSandboxAdoption: true,
expectedAdoptedSandbox: "not-ready-1",
expectNewSandboxCreated: false,
expectSandboxAdoption: false,
expectNewSandboxCreated: true,
},
{
name: "retries on conflict when adopting sandbox",
Expand Down Expand Up @@ -1310,6 +1310,81 @@ func TestSandboxClaimCreationMetric(t *testing.T) {
})
}

func TestSandboxClaimSkipsNotReadyAdoptionCandidates(t *testing.T) {
scheme := newScheme(t)

template := &extensionsv1alpha1.SandboxTemplate{
ObjectMeta: metav1.ObjectMeta{Name: "test-template", Namespace: "default"},
Spec: extensionsv1alpha1.SandboxTemplateSpec{
PodTemplate: sandboxv1alpha1.PodTemplate{
Spec: corev1.PodSpec{
Containers: []corev1.Container{{Name: "workspace", Image: "img:v1"}},
},
},
},
}

claim := &extensionsv1alpha1.SandboxClaim{
ObjectMeta: metav1.ObjectMeta{
Name: "skip-claim", Namespace: "default",
UID: "skip-claim-uid",
},
Spec: extensionsv1alpha1.SandboxClaimSpec{
TemplateRef: extensionsv1alpha1.SandboxTemplateRef{Name: "test-template"},
},
}

poolNameHash := sandboxcontrollers.NameHash("test-pool")

// Not-Ready sandbox: no Ready condition at all (pod being recreated during rotation)
notReadySandbox := &sandboxv1alpha1.Sandbox{
ObjectMeta: metav1.ObjectMeta{
Name: "not-ready-sb", Namespace: "default",
CreationTimestamp: metav1.Now(),
Labels: map[string]string{
warmPoolSandboxLabel: poolNameHash,
sandboxTemplateRefHash: sandboxcontrollers.NameHash("test-template"),
},
OwnerReferences: []metav1.OwnerReference{{
APIVersion: "extensions.agents.x-k8s.io/v1alpha1", Kind: "SandboxWarmPool",
Name: "test-pool", UID: "wp-uid", Controller: ptr.To(true),
}},
},
Spec: sandboxv1alpha1.SandboxSpec{
Replicas: ptr.To(int32(1)),
PodTemplate: sandboxv1alpha1.PodTemplate{
Spec: corev1.PodSpec{Containers: []corev1.Container{{Name: "workspace", Image: "img:v1"}}},
},
},
// No Ready condition — simulates rotation state
Status: sandboxv1alpha1.SandboxStatus{},
}

reconciler := &SandboxClaimReconciler{
Client: fake.NewClientBuilder().
WithScheme(scheme).
WithObjects(template, claim, notReadySandbox).
WithStatusSubresource(claim).
Build(),
Scheme: scheme,
Recorder: record.NewFakeRecorder(10),
Tracer: asmetrics.NewNoOp(),
}

req := reconcile.Request{NamespacedName: types.NamespacedName{Name: "skip-claim", Namespace: "default"}}
_, err := reconciler.Reconcile(context.Background(), req)
require.NoError(t, err)

// The not-ready sandbox should NOT have been adopted.
var sb sandboxv1alpha1.Sandbox
err = reconciler.Get(context.Background(), types.NamespacedName{Name: "not-ready-sb", Namespace: "default"}, &sb)
require.NoError(t, err)
controllerRef := metav1.GetControllerOf(&sb)
if controllerRef != nil && controllerRef.UID == claim.UID {
t.Fatal("not-ready sandbox should not have been adopted by claim")
}
}

func newScheme(t *testing.T) *runtime.Scheme {
scheme := runtime.NewScheme()
if err := sandboxv1alpha1.AddToScheme(scheme); err != nil {
Expand Down