ENGR9881代写、Monitoring留学生代做、代写C++代写、代做C++程序语言

日期：2019-05-12 09:52

ENGR9881 Computer Networks GE

CN Workshop05: Monitoring

Due: Friday, 14 May 2019

Lab 5 is comprised of 4 tasks; Task 4 is worth 2 checkpoints, each other task is worth 1 checkpoint with,

each checkpoint contributing 1% towards your topic grade. Following completion of the checkpoints, a

copy of the source code and output for each task should be compiled into a single text file and uploaded to

the relevant submission box on FLO for moderation. Speak to your demonstrator if you are unsure how to

do this.

While discussion of programming tasks with fellow students in labs is welcome and encouraged, please be

mindful of the University's Academic Integrity policy and refrain from simply copying another student's

code (even if they agree!). You will gain a much greater understanding of the material if you take the time to

work through your own solutions, and you will be expected to be able to explain your code before being

awarded checkpoints. Remember, the demonstrators are there to help if you get stuck.

Objectives

Upon completing they lab, you should be able to:

Profile C programs to explore run time information to observe the time that programs take to run

Use optional debug statements to enable/disable debugging code

Use system functions (stat) to access file metadata to observe the time and date fields that are used by

files in the file system

Learning out comes;

LO2: Demonstrate the design and implementation of simple process and network level programs

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Talk 1

Write a program that calculates and prints the elapsed time of a loop to an accuracy of microseconds.

1. Use the structure timeval to store times form the following C header file;

#include <sys/time.h>

3. In a loop that executes 100 times

Use gettimeofday() to get the time

Iterate through a loop 1,000,000 times

Use gettimeofday() to get the clasped time

4. Calculate and print the time taken in microseconds for each loop and entire program

execution

See;

man 2 gettimeofday

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Task 2

Write a program that uses the function getopt() to parse command line options, print provided

options.

1. Call a function usage() if there are no command line arguments

2. With in a suitable loop (refer to the getopt man page for example code

1. Use getopt() to parse the command line options

2. With in a switch/case statement

1. Process arguments and print each option and argument

2. In the switch control structure set the default case and ‘?’ to call usage() if

incorrect arguments are provided

void usage () {

printf(“Usage: programname -f filename”);

}

See;

man 3 getopt

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Task 3

Write a program that uses stat() to collect the metadata about a file and print out each of the

fields, display all the relevant time and/or date related fields.

1. Use getopt() to provide a the command line argument of the file name

2. Use the following C header file;

#include <sys/stat.h>

3. Use stat() and the structure in the stat man page to find the metadata about the provided file

4. Print each of the time related elements of the structure with the appropriate format and

description;

struct stat {

dev_t st_dev; /* device inode resides on */

ino_t st_ino; /* inode's number */

mode_t st_mode; /* inode protection mode */

…

}

5. Using the above comments in the structure in the man page;

printf(“device inode resides on: ‘%d’\n”, file->st_dev);

printf(“inode’s number: ‘%d’\n”, file->st_ino);

printf(“inode’s number: ‘%d’\n”, file->st_ino);

…

6. How can the time stamp on files be used to determine performance and timing?

See;

man 2 stat

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Task 4

Copy the source code for task 1 and add DEBUG statements around the timing functionality to

allow optional use of timing.

Part 1

1. add a #define statement at the top of your code for DEBUG 1 for true and DEBUG 0 for

false

2. Use an if statement to allow for conditional execution of the timing functions

if (DEBUG) {

gettimeofday();

}

3. Collect run time information in the shell with the command time, for each of DEBUG 1

and DEBUG 0

? Part 2

4. add a #define statement at the top of your code for DEBUG

5. Use an #ifdef and #endif statement to allow for conditional compilation and execution of

the timing functions

#ifdef DEBUG

gettimeofday()

#endif

6. Collect run time information in the shell with the command time, for each of DEBUG 1

and DEBUG 0

Part 3

7. Is it possible to measure any difference between using the techniques in part 1 and part 2?

8. Is it possible to measure the difference in execution time with the command line time?

See;

man 2 stat

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