C++ High Performance

Deadlock

When using mutex locks to protect shared resources, there is a risk of getting stuck in a state called deadlock. A deadlock can happen when two threads are waiting for each other to release their locks. None of the threads can proceed and are stuck in a deadlock state. One condition that needs to be fulfilled for a deadlock to occur is that one thread that already holds a lock tries to acquire an additional lock. When a system grows and gets larger, it becomes more and more difficult to track all locks that might be used by all threads running in a system. This is one reason for always trying to minimize the use of shared resources, and this demonstrates the need for exclusive locking.

The following figure shows how two threads are ...