CST 334 Week 6

    This week, we explored common concurrency issues, focusing on deadlock and how to manage it. Deadlock occurs when threads block each other by holding resources that others need, and four conditions must be met for it to happen: mutual exclusion, hold-and-wait, no preemption, and circular wait. We discussed techniques to prevent deadlock, such as enforcing strict lock ordering and using atomic lock acquisition. A practical approach to avoid circular wait is to always acquire locks in a consistent order, which can be managed through lock address ordering. Additionally, hold-and-wait can be avoided by acquiring all necessary locks at once, although this can reduce concurrency.

    In addition to prevention, we also looked at methods like deadlock avoidance through intelligent scheduling, where the system ensures that conflicting threads never run simultaneously, and detecting and recovering from deadlock when it occurs. While deadlock detection and recovery are more common in database systems, prevention and avoidance strategies are often preferred in practice. Overall, the key takeaway is that careful design and a structured approach to resource locking can mitigate concurrency problems like deadlock, leading to more reliable and efficient multi-threaded applications.

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