Connections within an exclusive routing group can share physical routes with other members of the same group. However, the compiler guarantees that these routes are not shared with connections outside the group.
Exclusive routing groups are intended for functional safety and isolation, not performance. If NoC connections simply require a high bandwidth connection, this can be addressed by setting the QoS bandwidth accordingly, without using exclusive routing groups.
Because exclusive routing groups dedicate NoC resources exclusively to that group, use them sparingly. Excessive use of these groups can negatively impact the ability of the NoC Compiler to find a solution. This is particularly true on the VNoC where there are only two routes per VNoC column.
The following figure shows a QoS specification for two exclusive routing groups, Ex1 and Ex2.
These are routed along a VNoC column with fixed endpoints, the results shown in the following figure.
You can see that the M00/S00 route, and
the M02/S02 route share a section of the physical
route, because they belong to the same exclusive routing group. Route M01/S01 is routed using completely independent physical
resources.