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Accepted the suggested changes and commited.

Co-authored-by: Marco Voelz <voelzmo@users.noreply.github.com>

vertical-pod-autoscaler/README.md

@@ -296,10 +296,11 @@ Please note the usage of the following arguments to override default names and p
 
 You can then choose which recommender to use by setting `recommenders` inside the `VerticalPodAutoscaler` spec.
 
-### Override default values when OOM occurs
-The below parameters can be used to overwrite the default values when an OOM event is occurred. When VPA observes an OOM it will use a sample that higher of:
-`oom-bump-up-ratio` specifies times the memory usage observed during OOM.
-`oom-min-bump-up-bytes` specifies minimal increase of memory after observing OOM.
+### Custom memory bump-up after OOMKill
+After an OOMKill event was observed, VPA increases the memory recommendation based on the observed memory usage in the event according to this formula: `recommendation = memory-usage-in-oomkill-event + max(oom-min-bump-up-bytes, memory-usage-in-oomkill-event * oom-bump-up-ratio)`. 
+You can configure the minimum bump-up as well as the multiplier by specifying startup arguments for the recommender:
+`oom-bump-up-ratio` specifies the memory bump up ratio when OOM occurred, default is `1.2`. This means, memory will be increased by 20% after an OOMKill event.
+`oom-min-bump-up-bytes` specifies minimal increase of memory after observing OOM. Defaults to `100 * 1024 * 1024` (=100MiB)
 
 Usage in recommender deployment
 ```

vertical-pod-autoscaler/pkg/recommender/main.go

@@ -66,8 +66,8 @@ var (
 	memoryAggregationIntervalCount = flag.Int64("memory-aggregation-interval-count", model.DefaultMemoryAggregationIntervalCount, `The number of consecutive memory-aggregation-intervals which make up the MemoryAggregationWindowLength which in turn is the period for memory usage aggregation by VPA. In other words, MemoryAggregationWindowLength = memory-aggregation-interval * memory-aggregation-interval-count.`)
 	memoryHistogramDecayHalfLife   = flag.Duration("memory-histogram-decay-half-life", model.DefaultMemoryHistogramDecayHalfLife, `The amount of time it takes a historical memory usage sample to lose half of its weight. In other words, a fresh usage sample is twice as 'important' as one with age equal to the half life period.`)
 	cpuHistogramDecayHalfLife      = flag.Duration("cpu-histogram-decay-half-life", model.DefaultCPUHistogramDecayHalfLife, `The amount of time it takes a historical CPU usage sample to lose half of its weight.`)
-	oomBumpUpRatio                 = flag.Float64("oom-bump-up-ratio", model.DefaultOOMBumpUpRatio, `The bump up ratio when OOM occurred, default is 1.2`)
-	oomMinBumpUp                   = flag.Float64("oom-min-bump-up-bytes", model.DefaultOOMMinBumpUp, `Specifies minimal increase of memory after observing OOM., default is 100 * 1024 * 1024`)
+	oomBumpUpRatio                 = flag.Float64("oom-bump-up-ratio", model.DefaultOOMBumpUpRatio, `The memory bump up ratio when OOM occurred, default is 1.2.`)
+	oomMinBumpUp                   = flag.Float64("oom-min-bump-up-bytes", model.DefaultOOMMinBumpUp, `The minimal increase of memory when OOM occurred in bytes, default is 100 * 1024 * 1024`)
 )
 
 func main() {

vertical-pod-autoscaler/pkg/recommender/model/aggregations_config.go

@@ -51,9 +51,9 @@ type AggregationsConfig struct {
 	// CPUHistogramDecayHalfLife is the amount of time it takes a historical
 	// CPU usage sample to lose half of its weight.
 	CPUHistogramDecayHalfLife time.Duration
-	// OOMBumpUpRatio specifies how much memory will be added after observing OOM.
+	// OOMBumpUpRatio specifies the memory bump up ratio when OOM occurred.
 	OOMBumpUpRatio float64
-	// OOMMinBumpUp specifies minimal increase of memory after observing OOM.
+	// OOMMinBumpUp specifies the minimal increase of memory when OOM occurred in bytes.
 	OOMMinBumpUp float64
 }
 
@@ -75,10 +75,10 @@ const (
 	// DefaultCPUHistogramDecayHalfLife is the default value for CPUHistogramDecayHalfLife.
 	// CPU usage sample to lose half of its weight.
 	DefaultCPUHistogramDecayHalfLife = time.Hour * 24
-	// DefaultOOMBumpUpRatio specifies how much memory will be added after observing OOM.
-	DefaultOOMBumpUpRatio float64 = 1.2
-	// DefaultOOMMinBumpUp specifies minimal increase of memory after observing OOM.
-	DefaultOOMMinBumpUp float64 = 100 * 1024 * 1024 // 100MB
+	// DefaultOOMBumpUpRatio is the default value for OOMBumpUpRatio.
+	DefaultOOMBumpUpRatio float64 = 1.2 // Memory is increased by 20% after an OOMKill.
+	// DefaultOOMMinBumpUp is the default value for OOMMinBumpUp.
+	DefaultOOMMinBumpUp float64 = 100 * 1024 * 1024 // Memory is increased by at least 100MB after an OOMKill.
 )
 
 // GetMemoryAggregationWindowLength returns the total length of the memory usage history aggregated by VPA.