Type-XDP SnapMirror transfers in fan-out topology are slower than expected

A SnapMirror source node has one or more slower fan-out SnapMirror relationships as well as other, faster fan-out SnapMirror Relationships from the same source node.
In some cases, one or more of the slower SnapMirror relationship(s) throttle the throughput rate achieved by the faster SnapMirror relationships.
- When the slower SnapMirrors are aborted or otherwise idle, the faster SnapMirror relationships go back to expected speeds.
- Note:
  - This KB only applies when fast SnapMirrors are throttled by slower SnapMirrors transferring from the same source node at the same time.
  - In these cases, the fast SnapMirrors run at expected speeds when the slower SnapMirrors are aborted or otherwise not transferring.
As an example, consider a SnapMirror source node has an InterCluster SnapMirror relationship going over a WAN link achieving at-best a throughput of 15MB/s.
- This same SnapMirror source node also has an intra-cluster SnapMirror relationship replicating over a 10Gbps cluster interconnect achieving a throughput of 100MB/s.
- When the slower InterCluster SnapMirror is transferring, the faster intra-cluster SnapMirror slows to ~15-20MB/s.
- When the slower InterCluster SnapMirror is aborted, the faster intra-cluster SnapMirror picks back up to the expected 100MB/s throughput.