Veeupup/distributed-system-and-database

CMU 15445 concurrency control问题讨论

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xffxff commented
  1. 为什么当其他事务也对某rid申请upgrade锁的时候，需要abort呢？

LockUpgrade: This should also abort the transaction and return false if another transaction is already waiting to upgrade their lock.

  1. LockManager RunCycleDetection()在什么地方调用呢？在哪儿启动它？
  2. RunCycleDetection如何abort一个transaction呢？只能得到需要abort的transaction id，lock manager又没有transaction manager属性。在lock manager中添加transaction manager类型attribute？
  3. LockManager abort的处理方式问题，setting transaction state to ABORT and return false 还是throw an exception