@Sklass, Sascha
Ingress traffic for the Account is the total amount of ingress data for the storage account across Blob, File, Queue, and Table services. This would include anything that is being uploaded or transferred to the storage account. Egress would be any data being downloaded or transferred out of the storage account. For more information and descriptions of the metrics you can refer to the documentation here. I am not sure looking at the Avg aggregation here is too helpful, better to look at the Sum and divide by the granularity in seconds to get the per second metric. To understand the limitations for the storage account performance please refer to the page here.
Hope this helps. Let us know if you have further questions or issues an we will be happy to help.
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