Difference between user-level and kernel-supported threads?

Question

I\'ve been looking through a few notes based on this topic, and although I have an understanding of threads in general, I\'m not really to sure about the differences bet

Answer 1

User Threads

1. The library provides support for thread creation, scheduling and management with no support from the kernel.
2. The kernel unaware of user-level threads creation and scheduling are done in user space without kernel intervention.
3. User-level threads are generally fast to create and manage they have drawbacks however.
4. If the kernel is single-threaded, then any user-level thread performing a blocking system call will cause the entire process to block, even if other threads are available to run within the application.
5. User-thread libraries include POSIX Pthreads, Mach C-threads, and Solaris 2 UI-threads.

Kernel threads

1. The kernel performs thread creation, scheduling, and management in kernel space.
2. kernel threads are generally slower to create and manage than are user threads.
3. the kernel is managing the threads, if a thread performs a blocking system call.
4. A multiprocessor environment, the kernel can schedule threads on different processors. 5.including Windows NT, Windows 2000, Solaris 2, BeOS, and Tru64 UNIX (formerlyDigital UN1X)-support kernel threads.