Use CSV format for Query Perf

[agrare]

There are two format types available for the QueryPerf method to request
metrics, normal and CSV. Normal formats are pre-parsed but are much
more verbose compared to the CSV format which leads to much higher
metrics capture times when using the normal format.

cc @Fryguy @dmetzger57

[Fryguy]

@dmetzger57 can you do an analysis on this to see how much better it is? I am good with this to merge since it's a big improvement in our demos, but let's also investigate if we can use split(","), which showed even better results.

[agrare]

Had to convert the miq_vim_perf_history to match the csv response format, metrics_capture_spec passes locally for me now :)

[dmetzger57]

Results based on 12 hour runs on Master and Master + PR, show a 29% improvement per capture. Data showed the total time savings was driven by Vim_execute_time improvement, which was the expected result. Perf_processing time increased slightly with the change, which was also anticipated as a result having to perform the CSV processing, however savings on Vim_execute_time more than made up for this.

Following are the averages for captures during the 12 hour runs.

Version	Total_time	Vim_execute_time	Vim_connect	Capture_intervals	Capture_counters	Build_query_params	Perf_processing
Master	0.3434511	0.1460997	0.0372707	0.0078682	0.0801656	0.0012391	0.0405987
Master with PR	0.2439322	0.0245613	0.0391695	0.0088154	0.0885660	0.0014192	0.0523345

[dmetzger57]

Data shows lower C&U Metrics Collector Worker PSS usage with the PR while collecting metrics for a 10,000 VM environment.

[kbrock]

This was tested in the POC. Ran quicker and used up less memory.

Going with using the CSV parser is the more conservative route.

Think the failure is due to master changes.

[miq-bot]

Checked commits agrare/manageiq-providers-vmware@81d2bc7~...2b6c6b5 with ruby 2.2.6, rubocop 0.47.1, and haml-lint 0.20.0
1 file checked, 0 offenses detected
Everything looks fine. 🍰

[agrare]

Finally green 🎉 /cc @Fryguy

[kbrock]

Yay Green!