(b) Consider the following scheme to reduce message traffic in distributed deadlock detection. Transactions are assigned unique priorities, and an antagonistic conflict occurs when a transaction waits for a data object that is locked by a lower priority transaction. Deadlock detection is initiated only when an antagonistic conflict occurs. When a waiting transaction; (i) Determine the number of messages exchanged to detect a deadlock in the ‘best’ case. (ii) Determine the number of messages exchanged to detect a deadlock in the ‘average’ case. (iii) Determine the number of messages exchanged to detect a deadlock in the ‘worst-case’ (iv) Determine the saving (in percentage) in the average number of messages exchanged under this message traffic reduction scheme as compared to when no such is used
(b) Consider the following scheme to reduce message traffic in distributed deadlock detection. Transactions are assigned unique priorities, and an antagonistic conflict occurs when a transaction waits for a data object that is locked by a lower priority transaction. Deadlock detection is initiated only when an antagonistic conflict occurs. When a waiting transaction;
(i) Determine the number of messages exchanged to detect a deadlock in the ‘best’ case.
(ii) Determine the number of messages exchanged to detect a deadlock in the ‘average’ case.
(iii) Determine the number of messages exchanged to detect a deadlock in the ‘worst-case’
(iv) Determine the saving (in percentage) in the average number of messages exchanged under this message traffic reduction scheme as compared to when no such is used
(c) Why does the interrupt disable method to achieve mutual exclusion not work for multiprocessor systems?
(d) Consider a magnetic disk consisting of 16 heads and 400 cylinders. This disk has four 100-cylinder zones with the cylinders in different zones containing 160, 200, 240. And 280 sectors, respectively. Assume that each sector contains 512 bytes, average seek time between adjacent cylinders is 1 msec, and the disk rotates at 7200 RPM. Calculate the: disk capacity, optimal track skew, maximum data transfer rate
Step by step
Solved in 2 steps
