[CM] Improve memory allocation with buffer variables

[saikishor]

This PR tries to address the issue of memory allocation in the RT loop of the CM read, write, and update cycles

[codecov]

Codecov Report

Attention: Patch coverage is 97.14286% with 1 line in your changes missing coverage. Please review.

Project coverage is 88.03%. Comparing base (52a2ffd) to head (58386ae).

Files with missing lines	Patch %	Lines
.../include/controller_manager/controller_manager.hpp	92.30%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1801      +/-   ##
==========================================
+ Coverage   87.97%   88.03%   +0.05%     
==========================================
  Files         121      121              
  Lines       13232    13209      -23     
  Branches     1195     1191       -4     
==========================================
- Hits        11641    11628      -13     
+ Misses       1149     1141       -8     
+ Partials      442      440       -2     

Flag	Coverage Δ
unittests	88.03% <97.14%> (+0.05%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
controller_manager/src/controller_manager.cpp	75.59% <100.00%> (-0.34%)	⬇️
.../include/controller_manager/controller_manager.hpp	96.77% <92.30%> (-3.23%)	⬇️

... and 3 files with indirect coverage changes

[fmauch]

This seems fair. Is there a reason that you went for a quite large number to reserve memory for?

[gavanderhoorn]

Question: would using an RT-safe memory allocator not be a more scalable approach?

[mergify]

This pull request is in conflict. Could you fix it @saikishor?

[saikishor]

This seems fair. Is there a reason that you went for a quite large number to reserve memory for?

Good question, the part of the vectors I can reduce it. For the part of the string, I think we will need it, when you have a large setup and it helps when concatenating strings

[saikishor]

Question: would using an RT-safe memory allocator not be a more scalable approach?

@gavanderhoorn Sure, I wanted to keep it simple and isolated, so it's easier for others. No big reason apart from that. Let me know what you think

[bmagyar]

Question: would using an RT-safe memory allocator not be a more scalable approach?

Do you have some pointers for us? (no pun intended! :D )

[saikishor]

@gavanderhoorn do you have any pointers to improve this approach?