Concurrency Models: Threads & Locks

2021, Mar 12    

Threads & Locks ( Mutual Exclusion and Memory Models )

• Mutual exclusion: using locks to ensure that only one thread can access data at a time to ensure we don’t get into race conditions and deadlocks
• Solution for dealing with sections of code which is trying to make changes to Shared Mutable State is to synchronize those sections using locks.
• These sections are also called to as mutex, monitor, or critical section
  

Some rules that help us avoid race conditions, deadlock, and issues with memory visibility:

• Synchronize all access to shared variables.
• Both the writing and the reading threads need to use synchronization.
• Acquire multiple locks in a fixed, global order.
• Don’t call alien methods while holding a lock.
• Hold locks for the shortest possible amount of time.