Q1. Explain One-to-One Model.
Ans. The one-to-one model maps each user thread to a kernel thread. It provides more concurrency than the many-to-one model by allowing another thread to run when a thread makes a blocking system call. It also allows multiple threads to run in parallel on multiprocessors.
The only drawback to this model is that creating a user thread requires creating the corresponding kernel thread. Because the overhead of creating kernel threads can burden the performance of an application, most implementations of this model restrict the number of threads supported by the system.
Windows operating systems—including Windows 95, 98, NT, 2000, and XP— implement the one-to-one model, and Linux, along with the family.
Figure: One-to-One Model