fix(chart): webserver probes timeout and period.

[mikaeld]

Description

This PR fixes the default probes timeout and period values. Generally, timeoutSeconds should be smaller than periodSeconds. Here are a SO question addressing this issue and a blog post detailing the Liveness and Readiness Probes. Furthermore, some specific k8s implementations such as GKE do not allow timeoutSeconds > periodSeconds.

The timeout is the amount of time that Google Cloud waits for a response to a probe. Its value must be less than or equal to the check interval. Units are seconds.

Finally, the webserver probes are the only ones with default values where timeoutSeconds > periodSeconds.

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[hussein-awala]

Can you update the default values in the webserver deployment too?

airflow/chart/templates/webserver/webserver-deployment.yaml

Lines 206 to 209 in 73e0313

	initialDelaySeconds: {{ .Values.webserver.livenessProbe.initialDelaySeconds | default 15 }}
	timeoutSeconds: {{ .Values.webserver.livenessProbe.timeoutSeconds | default 30 }}
	failureThreshold: {{ .Values.webserver.livenessProbe.failureThreshold | default 20 }}
	periodSeconds: {{ .Values.webserver.livenessProbe.periodSeconds | default 5 }}

and

airflow/chart/templates/webserver/webserver-deployment.yaml

Lines 220 to 223 in 73e0313

	initialDelaySeconds: {{ .Values.webserver.readinessProbe.initialDelaySeconds | default 15 }}
	timeoutSeconds: {{ .Values.webserver.readinessProbe.timeoutSeconds | default 30 }}
	failureThreshold: {{ .Values.webserver.readinessProbe.failureThreshold | default 20 }}
	periodSeconds: {{ .Values.webserver.readinessProbe.periodSeconds | default 5 }}

[jedcunningham]

Just remove them instead. They'll never get used.

[hussein-awala]

LGTM

[potiuk]

Yep. Looks like those defaults are much more reasonable @jedcunningham @ephraimbuddy @dstandish -> do you recal (or maybe have some Astronomer setup for the chart) to know where the original settings were derived from ? Maybe there are good reasons the original settings were like that?

[jedcunningham]

I don't see anything interesting in the history, to be honest. These seem reasonable to me too.