作者charliejack (charliejack)
看板Grad-ProbAsk
標題[理工][os]台大電機CSIE 99
時間Mon Feb 7 23:21:57 2011
第19題
In the management of transactions, we adopt the following notations.
Operations in a schedule are executed from left to right. Rk(X) means
a read operation to Object X by transaction k. Wk(X) means a write operation
to object X by transaction k. which of the following schedules are
serializable?
(A)R1(A)R2(B)W1(A)W2(B)
(B)R1(A)W2(A)W1(B)R2(B)
(C)R1(A)W2(B)R1(B)W2(A)
(D)R1(A)R2(B)W1(B)W2(B)
(E)W1(A)R2(A)W2(B)R1(B)
我是用 Reader Write Problem 去解釋這個問題
所以答案只有A
請問R"1" 的1 是指1個process ID?
我唯一有印象transaction
是在log-structure 裡面 使用的 transaction
不知道有沒有什麼關聯?
請大大門指點迷津
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 61.231.64.18
※ 編輯: charliejack 來自: 61.231.64.18 (02/07 23:23)
→ privatewind:這與reader writer problem無關 02/08 12:18
→ privatewind:應該是用time-stamp based 去解吧 02/08 12:19
→ charliejack:MM Thx 02/08 17:49