問題有點多... 1. Suppose the linux scheduler choose the process with the most credits to run, and if no runnable processes can be chosen , the recrediting operating is pf=erformed according to the following rule for every process in the system: credits = credits/2 + priority for each time slice, currently running process will lose one credit. When the credits reach zero, itis suspended. According to the above description, which of the following statements is correct? a)this credit system gives high priority to cpu-bound process b)the scheduling will exhibit short response time c)interactive processes will receive fewer eredits than non-i/o bound process d)none of the above 2. In operating systems the scheduler performs a rescheduling when current process request an I/O, the time slice assignedto current process is exhausted, the current process yields, or higher-priority process arrive. One every rescheduling , it will take time for the kernel to perform context switch.It it possible for a round-robin scheduler with a 100 millisecond time slices to spend over half its time in the OS context switch code? Assume that it take the OS 1 millisecond to context switch the CPU. Please justify your answer and give an example. 3. consider a system with three resource types with the vector Avalable initialized to (7,2,6).Suppose at time T0, process A has the resource vector of (0,1,2),process B has the resource vector of (2,0,0),and process C has the resource vector of (3,0,3). If process A requests for extra resource vector of (3,0,0), it is blocked since not enough resource available for allocation. Which necessary condition cannot occur for not enough resource available for allocation. Which necessary condition cannot occur for not entering deadlock state? a)process B asks for extra(0,1,1) and process C asks for extra (4,0,0) b)process B asks for extra(0,1,1) and process C asks for extra (0,0,1) c)process B asks for extra(4,1,2) and process C asks for extra (0,0,1) d)process B asks for extra(5,2,5) and process C asks for extra (2,1,0) e)none of the above 麻煩幫忙了，謝謝 --

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