[clangd] ignore parallelism level for quick tasks

Authored by qchateau on Jan 25 2021, 1:56 PM.


[clangd] ignore parallelism level for quick tasks

This allows quick tasks without dependencies that
need to run fast to run ASAP. This is mostly useful
for code formatting.

This fixes something that's been annoying me:

  • Open your IDE workspace and its 20 open files
  • Clangd spends 5 minutes parsing it all
  • In the meantime you start to work
  • Save a file, trigger format-on-save, which hangs because clangd is busy
  • You're stuck waiting until clangd is done parsing your files before the formatting and save takes place

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D94875