Hello @李想
welcome to this moderated Azure community forum.
according to the documentation, You need to scale up the number of units:
Number of partitions per event hub (Premium): 100 per event hub, but there's a limit of 200 per PU at the namespace level. For example, if a namespace is assigned 2 PUs, the limit for total number of partitions in all event hubs in the namespace is 2 * 200 = 400.
For premium, there is no throughput limitation:
Throughput per unit (Premium): No limits per PU (Depends on various factors such as resource allocation, number of partitions, storage, and so on.)
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