feature: Add environment variable controlling the log grooming frequency

[stefankeidel]

We've recently run into an issue where log grooming sidecar containers in our Airflow Kubernetes pods are incurring an absurd amount of transaction costs. That is because the log grooming process runs on a fixed, and for some use cases way too frequent schedule. We've hacked around it for now by overwriting the cleanup shell script in our custom Docker image, but I figured I would add a feature upstream that makes this configurable.

Let me know if there's anything I missed!

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[stefankeidel]

I am not entirely sure how the automation works that gets this change into the Dockerfile but I hope it's some CI/CD action. If there's anything else I need to run, let me know please :)

[nevcohen]

Hi, looks good!

I would love to understand why it makes a difference if it runs every 15 minutes or every hour (for example)?

How does this affect the worker performance?

[stefankeidel]

Hi, looks good!

I would love to understand why it makes a difference if it runs every 15 minutes or every hour (for example)?

How does this affect the worker performance?

Thanks for taking a look!

I personally wouldn't think it'd affect worker performance at all, since all they do is write to that file system. If anything it could see it improving because the volumes are not busy listing files all the time. But then again, I'm not super familiar with all the different types of setups Airflow can be run in.

In our case, extensive pruning on that shared volume was a) a major performance hog - we're dealing with Azure Blob Storage as backend, which is fairly slow to do a recursive find looking for last modified times and b) a major cost factor (ListBlob transactions get pricey). And our Airflow setup is not that large, maybe ~100 DAGs or so.

I broke one of the helm chart unit tests in the process here it seems. Will be attempting to deal with that this morning, but I need a working local setup first :)

[nevcohen]

Hi, looks good!

I would love to understand why it makes a difference if it runs every 15 minutes or every hour (for example)?

How does this affect the worker performance?

Thanks for taking a look!

I personally wouldn't think it'd affect worker performance at all, since all they do is write to that file system. If anything it could see it improving because the volumes are not busy listing files all the time. But then again, I'm not super familiar with all the different types of setups Airflow can be run in.

In our case, extensive pruning on that shared volume was a) a major performance hog - we're dealing with Azure Blob Storage as backend, which is fairly slow to do a recursive find looking for last modified times and b) a major cost factor (ListBlob transactions get pricey). And our Airflow setup is not that large, maybe ~100 DAGs or so.

I broke one of the helm chart unit tests in the process here it seems. Will be attempting to deal with that this morning, but I need a working local setup first :)

Got it, thanks! I would love to do CR for you :)