Bridge Crossing Example(过桥的例子) Traffic only in one direction.(只有一个方向) Each section of a bridge can be viewed as a resource (桥的每一个部分都可以看成资源) e If a deadlock occurs, it can be resolved if one car backs up (preempt resources and rollback). (如果死锁发生,它可以由一辆车返回而解决,抢占资源并回退 Several cars may have to be backed upif a deadlock occurs (如果死锁发生,可能很多车都不得不返回) Starvation is possible.(有可能产生饥饿) Applied Operating System Concepts 83 Silberschatz, GalVin, and Gagne@1999Silberschatz ,Galvin, and Gagne©1999 8.3 Applied Operating System Concepts Bridge Crossing Example（过桥的例子） • Traffic only in one direction.（只有一个方向） • Each section of a bridge can be viewed as a resource. （桥的每一个部分都可以看成资源） • If a deadlock occurs, it can be resolved if one car backs up (preempt resources and rollback). （如果死锁发生，它可以由一辆车返回而解决，抢占资源并回退） • Several cars may have to be backed upif a deadlock occurs. （如果死锁发生，可能很多车都不得不返回） • Starvation is possible.（有可能产生饥饿）