I have configured 1 Gb per VF maximum rate and it works. But when I configured 5 Gb rate limit on tx-0 or VF, I was able to get 5 Gb bitrate. I am curious that how a queue limit should exceed the limit of the VF port. The same behavior I observed with OVS police action.
Could you show your config commands and the test result.
So we can check and understand your question better.