●●● ●●●● 6.1 Background ●●●●● ●●●● ●●0●● ●●●0 Race condition(竟争状态读写的交错情形)°° The situation where several processes access and manipulate shared data concurrent o The final value of the shared data depends upon which process finishes last Solution---Synchronized Concurrent process must be synchronized To prevent race conditions and maintain data consistency requires mechanisms to ensure the orderly execution of cooperating processes ( serialization在临界区串行化) How8 6.1 Background ⚫ Race condition （竞争状态---读写的交错情形） ⚫ The situation where several processes access and manipulate shared data concurrently. ⚫ The final value of the shared data depends upon which process finishes last. ⚫ Solution---Synchronized ⚫ Concurrent process must be synchronized ⚫ To prevent race conditions and maintain data consistency requires mechanisms to ensure the orderly execution of cooperating processes (serialization 在临界区串行化) ⚫ How ？