What are the differences between locks and semaphores?

What are the differences between locks and semaphores?

Locks and semaphores are both synchronization primitives used in concurrent programming, but they serve different purposes. A lock allows only one thread to access a resource at a time, while a semaphore can allow multiple threads to access a limited number of resources.

Can you give me an example of when to use a lock?

Sure! Use a lock when you need to protect a critical section of code that modifies shared data, ensuring that only one thread can execute that section at a time.

And when would I use a semaphore instead?

You would use a semaphore when you want to control access to a pool of resources, like a fixed number of database connections, allowing multiple threads to use them concurrently up to a specified limit.

Are there any downsides to using locks?

Yes, using locks can lead to issues like deadlocks, where two or more threads are waiting indefinitely for each other to release locks. It's important to design your locking strategy carefully.

What about semaphores? Do they have downsides too?

Yes, semaphores can also lead to issues like starvation, where some threads may never get access to the resources if others keep acquiring them. Proper management is crucial.