Improve bottleneck analysis: language-specific suggestions

[saraadams]

Problem

The bottleneck analysis only highlights bottlenecks. It would be good to include more concrete guidance.

Suggested solution

• detect language based on known mnemonics:
  • event of category action processing
  • check for mnemonic in args array
• differentiate depending on menemonics
  • Java: break up large targets (BUILD file modification)
  • Cpp: break up large files (source code modification)
  • other languages?

Example mnemonics:

• CppCompile
• GoCompilePkg
• Javac
• Rustc

Mnemonics could be extracted from commonly used rules for different languages.

[saraadams]

https://stackoverflow.com/questions/44494170/is-there-a-way-to-see-the-mnemonics-of-bazel-actions-that-are-running gives suggestions on how to find mnemonics.