Kusto ingestion limit and command throttle because of capacity policy

Solution 1:

Effectively the document means that ingest capacity (in terms of concurrent ingest operations) is 3/4 times the overall number of cores in the cluster, but not higher than 512. You can view your cluster capacity and its utilization by running '.show cluster capacity' command.

If you do not want to handle the throttling by yourself, you should use the KustoQueuedIngestClient class, and pass to it the ingestion service endpoint (https://ingest-..kusto.windows.net). The ingestion service will take care of managing the load on your cluster. See Ingestion Overview article for more details.