The error Sysinfo error on operation returned status : Bad parameter. Please see the VMkernel log for detailed error information occurs if DRS generates a new set of resource settings for a given resource pool but vpxa is not able to apply them to the virtual machines. This can happen if the virtual machine is in a state where resource update is not allowed (for example, it is in the middle of a migration or a VCB backup).
If this message occurs for an extended period of time, research further into the cause. If the virtual machine is in the middle of an operation, you can ignore the message.
If the virtual machine is not in a state that prevents the resource update, then the resource setting that DRS generated has a circular dependency. This issue is resolved in ESXi 5.x. To workaround this issue in ESX/ESXi 4.1, set the parent resource pool to expandable instead of limited.