CO |Gate-2009| Computer Organization
- A CPU generally handles an interrupt by executing an interrupt service routine : [GATE – 2009]
a. As soon as an interrupt is raised.
b. By checking the interrupt register at the end of fetch cycle.
c. By checking the interrupt register after finishing the execution of the current instruction.
d. By checking the interrupt register at fixed time intervals.
Answer : c)
- Consider a 4 stage pipeline processor. The number of cycles needed by the four instructions I1, I2, I3, I4 in stages S1, S2, S3, S4 is shown below:
| S1 | S2 | S3 | S4 | |
| I1 | 2 | 1 | 1 | 1 |
| I2 | 1 | 3 | 2 | 2 |
| I3 | 2 | 1 | 1 | 3 |
| I4 | 1 | 2 | 2 | 2 |
What is the number of cycles needed to execute the following loop? For (i=1 to 2) {I1; I2; I3; I4;} [GATE – 2009]
a. 16
b. 23
c. 28
d. 30
Answer : b)
- Consider a 4-way set associative cache (initially empty) with total 16 cache blocks. The main memory consists of 256 blocks and the request for memory blocks is in the following order: 0, 255, 1, 4, 3, 8, 133, 159, 216, 129, 63, 8, 48, 32, 73, 92, 155. Which one of the following memory block will NOT be in cache if LRU replacement policy is used? [GATE – 2009]
a. 3
b. 8
c. 129
d. 216
Answer : d)
- A hard disk has 63 sectors per track, 10 platters each with 2 recording surfaces and 1000 cylinders. The address of a sector is given as a triple <c,h,s>, where c is the cylinder number, h is the surface number and s is the sector number. Thus, the 0th sector is addressed as 0, 0, 0 , the 1st sector as 0, 0,1 , and so on The address <400, 16, 29> corre4sponds tp sector number : [GATE – 2009]
a. 505035
b. 505036
c. 505037
d. 505038
Answer : c)
- A hard disk has 63 sectors per track, 10 platters each with 2 recording surfaces and 1000 cylinders. The address of a sector is given as a triple c, h, s , where <c,h,s>, where c is the cylinder number, h is the surface number and s is the sector number. Thus, the 0th sector is addressed as 0, 0, 0 , the 1st sector as 0, 0,1 , and so on . The address of the 1039 th sector is : [GATE – 2009]
a. <0, 16, 31>
b. <0, 16, 30>
c. <0, 15, 31>
d. <0, 17, 31>
Answer : a)
CO |Gate-2009|