Hi,
Currently we do not have this feature supported to identify specific share using PA, given that one can identify the clients( CIFS/NFS) who is causing performance degradation on the controller.
On NMC , go to Monitor->client statistics-->choose the controller of interest from the HOST list-->click client statistics for the time period of Interest. Once the top five clients are identified which are causing performance degradation on the controller,user can look at the shares/nfs mounts on those clients and mapped to the corresponding qtrees and take necessary action.