A conventional queue or topic is handled by a single message broker and stored in one messaging store. Supported only in the Basic and Standard messaging tiers, a partitioned queue, or topic is handled by multiple message brokers and stored in multiple messaging stores. This feature means that the overall throughput of a partitioned queue or topic is no longer limited by the performance of a single message broker or messaging store. Also, a temporary outage of a messaging store doesn't render a partitioned queue or topic unavailable.
Ordering isn't ensured when using partitioned entities. In the event that a partition is unavailable, you can still send and receive messages from the other partitions.
Partitioned entities are no longer supported in the Premium SKU.