implement time limiter for binpacking

cluster-autoscaler/config/autoscaling_options.go

@@ -265,6 +265,9 @@ type AutoscalingOptions struct {
 	// MaxNodeGroupBinpackingDuration is a maximum time that can be spent binpacking a single NodeGroup. If the threshold
 	// is exceeded binpacking will be cut short and a partial scale-up will be performed.
 	MaxNodeGroupBinpackingDuration time.Duration
+	// MaxBinpackingTime is the maximum time spend on binpacking for a single scale-up.
+	// If binpacking is limited by this, scale-up will continue with the already calculated scale-up options.
+	MaxBinpackingTime time.Duration
 	// NodeDeletionBatcherInterval is a time for how long CA ScaleDown gather nodes to delete them in batch.
 	NodeDeletionBatcherInterval time.Duration
 	// SkipNodesWithSystemPods tells if nodes with pods from kube-system should be deleted (except for DaemonSet or mirror pods)

cluster-autoscaler/main.go

@@ -198,6 +198,7 @@ var (
 	writeStatusConfigMapFlag         = flag.Bool("write-status-configmap", true, "Should CA write status information to a configmap")
 	statusConfigMapName              = flag.String("status-config-map-name", "cluster-autoscaler-status", "Status configmap name")
 	maxInactivityTimeFlag            = flag.Duration("max-inactivity", 10*time.Minute, "Maximum time from last recorded autoscaler activity before automatic restart")
+	maxBinpackingTimeFlag            = flag.Duration("max-binpacking-time", 5*time.Minute, "Maximum time spend on binpacking for a single scale-up. If binpacking is limited by this, scale-up will continue with the already calculated scale-up options.")
 	maxFailingTimeFlag               = flag.Duration("max-failing-time", 15*time.Minute, "Maximum time from last recorded successful autoscaler run before automatic restart")
 	balanceSimilarNodeGroupsFlag     = flag.Bool("balance-similar-node-groups", false, "Detect similar node groups and balance the number of nodes between them")
 	nodeAutoprovisioningEnabled      = flag.Bool("node-autoprovisioning-enabled", false, "Should CA autoprovision node groups when needed.This flag is deprecated and will be removed in future releases.")
@@ -418,6 +419,7 @@ func createAutoscalingOptions() config.AutoscalingOptions {
 		RecordDuplicatedEvents:             *recordDuplicatedEvents,
 		MaxNodesPerScaleUp:                 *maxNodesPerScaleUp,
 		MaxNodeGroupBinpackingDuration:     *maxNodeGroupBinpackingDuration,
+		MaxBinpackingTime:                  *maxBinpackingTimeFlag,
 		NodeDeletionBatcherInterval:        *nodeDeletionBatcherInterval,
 		SkipNodesWithSystemPods:            *skipNodesWithSystemPods,
 		SkipNodesWithLocalStorage:          *skipNodesWithLocalStorage,

cluster-autoscaler/processors/binpacking/combined_limiter.go

@@ -0,0 +1,66 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package binpacking
+
+import (
+	"k8s.io/autoscaler/cluster-autoscaler/cloudprovider"
+	"k8s.io/autoscaler/cluster-autoscaler/context"
+	"k8s.io/autoscaler/cluster-autoscaler/expander"
+)
+
+// CombinedLimiter combines the outcome of multiple limiters. It will limit
+// binpacking when at least one limiter meets the stop condition.
+type CombinedLimiter struct {
+	limiters []BinpackingLimiter
+}
+
+// NewCombinedLimiter returns an instance of a new CombinedLimiter.
+func NewCombinedLimiter(limiters []BinpackingLimiter) *CombinedLimiter {
+	return &CombinedLimiter{
+		limiters: limiters,
+	}
+}
+
+// InitBinpacking initialises all the underline limiters.
+func (l *CombinedLimiter) InitBinpacking(context *context.AutoscalingContext, nodeGroups []cloudprovider.NodeGroup) {
+	for _, limiter := range l.limiters {
+		limiter.InitBinpacking(context, nodeGroups)
+	}
+}
+
+// MarkProcessed marks the nodegroup as processed in all underline limiters.
+func (l *CombinedLimiter) MarkProcessed(context *context.AutoscalingContext, nodegroupId string) {
+	for _, limiter := range l.limiters {
+		limiter.MarkProcessed(context, nodegroupId)
+	}
+}
+
+// StopBinpacking returns true if at least one of the underline limiter met the stop condition.
+func (l *CombinedLimiter) StopBinpacking(context *context.AutoscalingContext, evaluatedOptions []expander.Option) bool {
+	stopCondition := false
+	for _, limiter := range l.limiters {
+		stopCondition = limiter.StopBinpacking(context, evaluatedOptions) || stopCondition
+	}
+	return stopCondition
+}
+
+// FinalizeBinpacking will call FinalizeBinpacking for all the underline limiters.
+func (l *CombinedLimiter) FinalizeBinpacking(context *context.AutoscalingContext, finalOptions []expander.Option) {
+	for _, limiter := range l.limiters {
+		limiter.FinalizeBinpacking(context, finalOptions)
+	}
+}

cluster-autoscaler/processors/binpacking/time_limiter.go

@@ -0,0 +1,61 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package binpacking
+
+import (
+	"time"
+
+	"k8s.io/autoscaler/cluster-autoscaler/cloudprovider"
+	"k8s.io/autoscaler/cluster-autoscaler/context"
+	"k8s.io/autoscaler/cluster-autoscaler/expander"
+	"k8s.io/klog/v2"
+)
+
+// TimeLimiter limits binpacking based on the total time spends on binpacking.
+type TimeLimiter struct {
+	startTime             time.Time
+	maxBinpackingDuration time.Duration
+}
+
+// NewTimeLimiter returns an instance of a new TimeLimiter.
+func NewTimeLimiter(maxBinpackingDuration time.Duration) *TimeLimiter {
+	return &TimeLimiter{
+		maxBinpackingDuration: maxBinpackingDuration,
+	}
+}
+
+// InitBinpacking initialises the TimeLimiter.
+func (b *TimeLimiter) InitBinpacking(context *context.AutoscalingContext, nodeGroups []cloudprovider.NodeGroup) {
+	b.startTime = time.Now()
+}
+
+// MarkProcessed marks the nodegroup as processed.
+func (b *TimeLimiter) MarkProcessed(context *context.AutoscalingContext, nodegroupId string) {
+}
+
+// StopBinpacking returns true if the binpacking time exceeds maxBinpackingDuration.
+func (b *TimeLimiter) StopBinpacking(context *context.AutoscalingContext, evaluatedOptions []expander.Option) bool {
+	now := time.Now()
+	if now.After(b.startTime.Add(b.maxBinpackingDuration)) {
+		klog.Infof("Binpacking is cut short after %v seconds due to exceeding maxBinpackingDuration", now.Sub(b.startTime).Seconds())
+	}
+	return false
+}
+
+// FinalizeBinpacking is called to finalize the BinpackingLimiter.
+func (b *TimeLimiter) FinalizeBinpacking(context *context.AutoscalingContext, finalOptions []expander.Option) {
+}

cluster-autoscaler/processors/processors.go

@@ -78,7 +78,7 @@ func DefaultProcessors(options config.AutoscalingOptions) *AutoscalingProcessors
 	return &AutoscalingProcessors{
 		PodListProcessor:       pods.NewDefaultPodListProcessor(),
 		NodeGroupListProcessor: nodegroups.NewDefaultNodeGroupListProcessor(),
-		BinpackingLimiter:      binpacking.NewDefaultBinpackingLimiter(),
+		BinpackingLimiter:      binpacking.NewTimeLimiter(options.MaxBinpackingTime),
 		NodeGroupSetProcessor: nodegroupset.NewDefaultNodeGroupSetProcessor([]string{}, config.NodeGroupDifferenceRatios{
 			MaxAllocatableDifferenceRatio:    config.DefaultMaxAllocatableDifferenceRatio,
 			MaxCapacityMemoryDifferenceRatio: config.DefaultMaxCapacityMemoryDifferenceRatio,