VPA: Default values are not correct in the generated docs for flags

[ialidzhikov]

Which component are you using?:
/area vertical-pod-autoscaler

What version of the component are you using?:

Component version: v0.13.0

What k8s version are you using (kubectl version)?:

kubectl version Output

$ kubectl version

What environment is this in?:

What did you expect to happen?:

Flags like --memory-aggregation-interval and --memory-aggregation-interval-count to have a correct default value in the generated docs.

What happened instead?:

In https://github.com/kubernetes/autoscaler/blob/master/vertical-pod-autoscaler/docs/flags.md, the default values for some flags are wrong.
For example, --memory-aggregation-interval has default value of 24h, --memory-aggregation-interval-count has default value of 8.

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

Lines 94 to 95 in da7f581

memoryAggregationInterval = flag.Duration("memory-aggregation-interval", model.DefaultMemoryAggregationInterval, `The length of a single interval, for which the peak memory usage is computed. Memory usage peaks are aggregated in multiples of this interval. In other words there is one memory usage sample per interval (the maximum usage over that interval)`)

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.`)

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

Lines 66 to 70 in 06e01ac

	// DefaultMemoryAggregationIntervalCount is the default value for MemoryAggregationIntervalCount.
	DefaultMemoryAggregationIntervalCount = 8
	// DefaultMemoryAggregationInterval is the default value for MemoryAggregationInterval.
	// which the peak memory usage is computed.
	DefaultMemoryAggregationInterval = time.Hour * 24

On the other side, in the docs these flags have 0 as default value:

autoscaler/vertical-pod-autoscaler/docs/flags.md

Lines 43 to 44 in d6fcca2

	| --memory-aggregation-interval | Duration | 0 | `The length of a single interval, for which the peak memory usage is computed. Memory usage peaks are aggregated in multiples of this interval. In other words there is one memory usage sample per interval (the maximum usage over that interval)` |
	| --memory-aggregation-interval-count | Int64 | 0 | `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.` |

How to reproduce it (as minimally and precisely as possible):

See above.

Anything else we need to know?:

N/A

[ialidzhikov]

cc @omerap12

[omerap12]

Yes, we have a pending PR that addresses this issue (though not entirely): #7642

We also plan to modify the process for generating the flag documentation, similar to what’s done with CA: Comment on PR #7642.

I plan to work on that but currently have capacity issue.

[omerap12]

Opened this: #7779