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05. [20p] Multitool Comparison

Now we will see in a slightly different approach, with a source file and a final file of the same size, how the I/O mechanisms work as they are implemented by the compiler to be optimized.

Nu cred ca are sens chestia asta. Putem sa lasam direct cele 2 task-uri.

(Modify the script so that it reads one line at a time from the file with the novel from the previous exercise, and writes it in a resulting file 500 times each. Follow the process with a classic tool (vmstat, iostat). Why most of the time the number of bytes read is 0?

TODO COSMIN: Aici pui un hidden script cu rezolvarea pt asistenti cum e la 4, in python o pui, verifica sa fie astfel incat sa tina linia in RAM.)

[10p] Task A - Different tool, same I/O

For more special situations, a classic tool is not enough as long as we want to have a more detailed analysis of the behavior of I/O mechanisms. An example would be to create an infinite loop that copies endlessly (simulation of a demanding process for a long time) a large file (use one of the files obtained previously).

Put the command below in a script:

$ while true; do cp original_file1 copied_file2; done

Use several special monitoring tools.

Choose 3-4 from here: https://www.golinuxcloud.com/monitor-disk-io-performance-statistics-linux/

[10p] Task B - Plot of Comparison

Plot a graph with the results obtained with iostat, iotop and one of the previously chosen tools. Interpret the graph and the values obtained using those tools.

  • basic plot
  • the values used should represent the same metric (eg: kb written per second)
  • you can take the values manually or automatically
  • standardize the values (kb/s)
  • preferably use the matplotlib module in python

ep/labs/03/contents/tasks/ex5.1596649454.txt.gz ยท Last modified: 2020/08/05 20:44 by gheorghe.petre2608
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