* queue - osp_device::opd_async_requests. When the queue is full, all the
* requests in the queue will be packaged into a single OUT RPC and given to
* the ptlrpcd daemon (for sending), then the queue is purged and other new
* queue - osp_device::opd_async_requests. When the queue is full, all the
* requests in the queue will be packaged into a single OUT RPC and given to
* the ptlrpcd daemon (for sending), then the queue is purged and other new