Add section detailing performance improvements to documentation

[rjwills28]

We ran some performance tests on Phoebus using multiple windows displaying 100s of PVs updating at 10Hz. We discovered that the displayed update rate was much slower than the actual PV update rate. After some further investigations we found that there are 2 environment variables that can be set which drastically improved the performance of the displays when running using hardware acceleration.

I have added a section to the Phoebus documentation detailing these variables and how to use them, just in case others should come across this issue and might benefit from this advice.

I think having this in the 'Starting CS-Studio/Phoebus' makes sense but if anyone has other ideas then please just let me know and I can move it.

Checklist

• Testing:

  • The feature has automated tests
  • Tests were run
  • If not, explain how you tested your changes

• Documentation:

  • The feature is documented
  • The documentation is up to date
  • Release notes:
    • Added an entry if the change is breaking or significant
    • Added an entry when adding a new feature

[kasemir]

Does this apply to any operating system or only to for example Linux?

[rjwills28]

Ah good question. Tested on Linux RedHat and Ubuntu OSs. Not tested on Windows. I can clarify that in the text.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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