joe111

If i knew the answer would i be posting them here? If you cant help don't bother replying, and don't lie about being a computer science student

4 (a) What are the five layers in the Internet protocol stack? What are the principal responsibilities of each of these layers? (10 marks) (b) Describe briefly the chain of events that occur when Alice types the URL for www.google.com into her web browser and that will eventually result in Google’s home page being displayed. Your answer should concentrate on the protocols that are used prior to the sending of the HTTP GET message to www.google.com. (6 marks) © With reference to the following Telnet session transcript give an explanation of the HTTP protocol: $ telnet www.cis.strath.ac.uk 80 Trying 130.159.196.40... Connected to www.cis.strath.ac.uk. Escape character is '^]'. GET / HTTP/1.1 Host: www.cis.strath.ac.uk HTTP/1.1 302 Found Date: Wed, 07 Apr 2010 10:36:48 GMT Server: Apache Location: http://www.strath.ac.uk/cis/ Content-Length: 282 Content-Type: text/html; charset=iso-8859-1 … (4 marks)

Can someone help me with my assignment please 3 (a) Two core ideas in operating systems are multiprogramming and timesharing/ multitasking. What does each of these ideas entail? What is the main motivation behind their introduction? (4 marks) (b) What are the different methods of passing system call parameters to the operating system? What are their respective advantages and disadvantages? (6 marks) © Given five memory partitions of 100 KB, 500 KB, 200 KB, 300 KB, and 600 KB (in order), how would each of the first-fit, best-fit, and worst-fit algorithms place processes of 212 KB, 417 KB, 112 KB, and 426 KB (in order)? Which algorithm makes the most efficient use of memory? (7 marks) (d) What is the cause of thrashing? How does the system detect thrashing? Once it detects thrashing, what can the system do to eliminate this problem? (3 marks)

Can anyone help me with my assignment please. thank you Consider the following function that forms part of a C program that has been written to measure the execution time of a simple arithmetic statement like sum = sum + increment; long sumLoop(long increment, long iterations) { long i, sum=0; for (i=0 ; i < iterations ; i++) { sum = sum + increment; } return (sum); } The following (numbered) lines of IA-32 (in GAS format) assembly language corresponding to the above function have been generated when the C program was compiled without optimisation: 10 sumLoop: 11 pushl %ebp 12 movl %esp, %ebp 13 subl $8, %esp 14 movl $0, -8(%ebp) 15 movl $0, -4(%ebp) 16 .L7: 17 movl -4(%ebp), %eax 18 cmpl 12(%ebp), %eax 19 jl .L10 20 jmp .L8 21 .L10: 22 movl 8(%ebp), %eax 23 leal -8(%ebp), %edx 24 addl %eax, (%edx) 25 leal -4(%ebp), %eax 26 incl (%eax) 27 jmp .L7 28 .L8: 29 movl -8(%ebp), %eax 30 leave 31 ret Where appropriate please refer to these corresponding line number(s) in your answers to the following questions: (a) Explain the purpose and/or operation of these assembly language statements in the context of this C function. Little credit will be given to answers that merely repeat what is obvious from each statement. For example, don't answer "pushes register ebp onto the stack" for line 11. (10 marks) (b) Outline a technique that a C programmer might use in an attempt to measure the execution time of a single sum = sum + increment; statement with a high degree of accuracy. Identify the issues in the technique you propose that may lead to inaccuracies in timing and discuss briefly how you would overcome these. (5 marks) © When the program is recompiled with optimisation (the –O3 compiler switch) the programmer discovers that the sumLoop () function runs faster and that the execution time of a sum = sum + increment; statement drops to 1 nanosecond in the optimised code from the original measurement of 5 nanoseconds in the non-optimised version of the program. Give an explanation of the optimisations that are likely to have been made by the compiler in order to achieve this fivefold improvement in performance and compare and contrast these optimisations with the original assembly code in the above listing. (5 marks)

Can anyone please help with this homework question. Thank you 1 (a) MIPS is a popular metric for rating the performance of a computer. In this context what does MIPS mean? (1 mark) (b) There are three types of MIPS ratings, namely: (i) Native MIPS (ii) Peak MIPS (iii) Relative MIPS Explain how each type is calculated and what their drawbacks may be. (9 marks) © Another derivation of MIPS used by a RISC research team at Stanford – some of whom went on to found the MIPS Company – was Microprocessor [without] Interlocked Pipeline Stages. This approach traded off simplicity in the hardware with complexity in the compiler and assembler for the machine. Highlight two issues that the compiler and/or the assembler (the software) would need to deal with in order to overcome the problems inherent in a non-interlocked pipeline. Give typical examples of the software techniques used to overcome these problem (4 marks) (d) Modern processor implementations now have hardware support to detect, and circumvent, the problems arising from pipelined datapaths. Describe two examples of the hardware techniques used to overcome these problems. (6 marks)