Kernel Write Bandwidth - 2022.2 English

Vitis Guidance Messaging (UG1315)

Document ID
UG1315
Release Date
2022-10-19
Version
2022.2 English

Description

Kernel write utilization on this specific port is too low.

Explanation

This message is generated whenever the runtime environment considers that the utilization of a port is too low. This can be a combination of port data width and burst inference.

Recommendation

If the data width of a port is far less than 512 bits, consider packaging multiple values into a single transfer. The 512 bits can be efficiently packed and unpacked on the receiving side by utilizing a separate process to read and write to the AXI interface.

These processes can also be used to effectively infer burst reads and writes. Each of these processes should contain a loop with a simple variable incremented by one to read/write from the port and store the value internally.

Applying the DATAFLOW pragma to these processes surrounding the algorithm results in an efficient implementation.