This post summarizes the progress in the Seventh week of the coding period. This week pcp-pidstat was merged with the pcp master. My first contribution to PCP.

PCP-Pidstat merged into PCP

Finally a big moment, pcp-pidstat getting merged into pcp was the first milestone in the journey of GSoC.
Since last week, the man-pages(1) were set and only thing left was to write regression tests.

Writing regression tests

pcp maintains a qa/ directory which has regression tests with a number; say N and N.out as a output file, which is checked by the ./check script present in the same directory. Regression test for pcp includes the following steps:

1. Create a new test file using ./new. It will create a new test with a suitable number.
2. The test file generated contains basic instructions to help to write the new test cases.
3. Create an archive using pmlogger which contains 3-4 samples to be used for the qa. Store it into the /qa/archives directory.
4. Write the test cases for various input commands and options.The script should use the archives store in the previous step.
5. Once the script is written, generate the N.out file using ./remake script. All the ./check script does is, it executes the commands from this script and tries to (near)match the output with the N.out file.

Overriding pcp options to match pcp-pidstat

One of the many good things pcp APIs provides is, provision to override default pcp options to perform different operations. After pcp-pidstat was merged, some pcp developers tried to use it and suggested using -p option same as the pidstat instead of -P. Then Nathan hinted an example about overriding default options. After looking at the example, I was able to replace that option. So far everything looks great! Thank you, Ryan and Nathan for the help so far. :)

That’s all folks.