06-01-2017 06:25 AM
In SDaccel there is a limit to the number of compute units that can be used (10 or 16). This refers to kernels connected to memory alone, is it not?
I have multiple kernels connected through pipes. Only one kernel is connected to the global memory.
I assumed using pipes will allow more compute units, but SDACCEL is throwing an error saying Max number of compute units exceeded.
Is this a bug? or Is this how it's supposed to be. Is there a workaround?
06-01-2017 11:20 AM
SDAccel allows a maximum of 10 compute units.
If your sdaccel_profile_summary.html Compute Unit Utilization section is showing less than 10 compute units and you are getting the error, send me the code to review.
This example shows how too many compute units can negatively impact performance and how a single compute unit can improve the design.
In this example, multiple compute units are used to improve the performance of the design.
06-02-2017 02:24 AM
At least 1 M_AXI and 1 S_AXI bus will be allocated for each kernel no matter whether they are connected to global memory or not.
SDAccel use these AXI buses to en-queue workload, set args and monitor kernel status.
Too many kernels produce huge complex buses and deteriorate timing performance and routability.
06-02-2017 09:27 AM
For kernels connecting to internal pipes, host intervention should not be needed. This is a good use case SDAccel should support as not only does it increase number of compute units but also get rid of overhead associated with AXI Lite/MM interfaces.