CPE 380 Exam 1

A particular program takes 300 seconds total to run and it spends 200 seconds performing divides. Assume we can speed up the division operation. How much faster would divides need to execute to reduce the total program running time to 150 seconds? Is it possible to reduce running time to 75 seconds? - Answer- 4 times faster, No Which of the following are problems with using Millions of Instructions Per Second (MIPS for short) as a measure for comparing computers' performance? - Answer- While MIPS specifies the instruction excution rate, it doesn't take into account what the instructions actually do. Different programs on the same computer will have different MIPS. If, for a given algorithm, a new program executes more instructions, but each instruction ends up being faster, MIPS can vary independently from performance. All of the above Which of the following components of performance refers to the average number of clock cycles per instruction? - Answer- Clock cycles per instruction (CPI) The number of clock cycles per second is referred to as the _______. - Answer- clock frequency (rate) The set of instructions decoded by the computer that provide the interface connecting the lowest-level software to the CPU hardware is the _______. - Answer- Instruction set architecture What is abstraction in computer design? - Answer- Making lower-level details hidden to present a simpler model for other levels. We use abstraction in computer design to improve: - Answer- the productivity What are the levels of abstraction in computer design? - Answer- problem, algorithm, programming language, ISA, microarchitecture, logic structures, transistor-level circuits, device ------ Performance is always defined as computational speed. - Answer- False A higher-level programming language, like C++ or Java, can compute more than a lower-level programming language, like a assembly. - Answer- False A 16-bit Intel 80286-based computer can compute as much as modern multi-core 64-bit x86 architecture if given enough time and memory. - Answer- True A program with 1.45E12 instructions takes 500 seconds to run on a 3.5 GHz processor.