Rescan HBA is taking long time

Hi,

           I have 2 Exsi host in the cluster. (say host A and host B) . I observed that the Rescan HBA is taking 8-9 min on host A using VIJAVA call (rescanHba api of HostStorageSystem ) where as Rescan HBA is smooth (taking few seconds only) if perform from vcenter server.

          Here wanted to know which logs of Exsi server should I use to figure out why Rescan HBA is taking time. OR Please sugget any other way of figuring out the problem.