Q. Presume an operating system maps user-level threads to the kernel using the many-to-many model and the mapping is done through LWPs. Additionally the system allows developers to create real-time threads. Is it essential to bind a real-time thread to an LWP? Elucidate.
Answer: Yes Timing is critical to real-time applications. If a thread is marked like real-time but is not bound to an LWP the thread may have to wait to be attached to an LWP previous to running. Regard as if a real-time thread is running (is attached to an LWP) in addition to then proceeds to block (i.e. must perform I/O has been pre-empted by a higher-priority real-time thread is waiting for a mutual exclusion lock etc.) While the real-time thread is blocked-up the LWP it was attached to has been assigned to another thread. While the real-time thread has been scheduled to run again it should first wait to be attached to an LWP. Through binding an LWP to a real time thread you are making sure the thread will be able to run with minimal delay once it is scheduled.