Process Synchronization

Question

Is there any difference between busy waiting and spinlock

What is the meaning of this statement

"advantage of a spinlock is that no context switch is required when a process must wait on lock, and a context switch may takes considerable time  Thus when locks are expected to be held for short time spinlock are useful"

I can't understand this statement

Please tell with example..

Comments

Spin lock and busy waiting are same..

Actually  using  busy waiting  solution  cause cpu time waste

But when locks are held for short time, we can afford  busy waiting because very short time a process run in that loop

Answer 1

Spin Lock is another term for busy waiting. Assume if context switching between processes takes x ms, and maximum amount of time a process needs to wait for a resource to be available be y ms, then its clearly noticeable that if y < x, then you're better off waiting than switching to some other process. So basically, what spin lock does is that it makes the process "spin" in a loop while waiting for the resource to be available.