Computer Architecture & Organization Questions GATE 2022

Computer Architecture & Organization GATE Question Answers with Explanation.

Q1 – Which one of the following facilitates transfer of bulk data from hard disk to main memory with the highest throughput? (GATE 2022)

DMA based I/O transfer
Interrupt driven I/O transfer
Polling based I/O transfer
Programmed I/O transfer

Ans – (1)

Explanation –

Q2 – Let R1 and R2 be two 4-bit registers that store numbers in 2’s complement form. For the operation R1+R2, which one of the following values of R1 and R2 gives an arithmetic overflow? (GATE 2022)

R1 = 1011 and R2 = 1110
R1 = 1100 and R2 = 1010
R1 = 0011 and R2 = 0100
R1 = 1001 and R2 = 1111

Ans – (2)

Explanation –

Q3 – A processor X₁ operating at 2 GHz has a standard 5-stage RISC instruction pipeline having a base CPI (cycles per instruction) of one without any pipeline hazards. For a given program P that has 30% branch instructions, control hazards incur 2 cycles stall for every branch. A new version of the processor X₂ operating at same clock frequency has an additional branch predictor unit (BPU) that completely eliminates stalls for correctly predicted branches.

There is neither any savings nor any additional stalls for wrong predictions. There are no structural hazards and data hazards for X₁ and X₂. If the BPU has a prediction accuracy of 80%, the speed up (rounded off to two decimal places) obtained by X₂ over X₁ in executing P is____________. (GATE 2022)

Ans – (1.42 to 1.45)

Explanation –