Alex Rickabaugh 48fec08c95 perf(compiler-cli): refactor the performance tracing infrastructure (#41125)
ngtsc has an internal performance tracing package, which previously has not
really seen much use. It used to track performance statistics on a very
granular basis (microseconds per actual class analysis, for example). This
had two problems:

* it produced voluminous amounts of data, complicating the analysis of such
  results and providing dubious value.
* it added nontrivial overhead to compilation when used (which also affected
  the very performance of the operations being measured).

This commit replaces the old system with a streamlined performance tracing
setup which is lightweight and designed to be always-on. The new system
tracks 3 metrics:

* time taken by various phases and operations within the compiler
* events (counters) which measure the shape and size of the compilation
* memory usage measured at various points of the compilation process

If the compiler option `tracePerformance` is set, the compiler will
serialize these metrics to a JSON file at that location after compilation is
complete.

PR Close #41125
2021-03-24 13:42:24 -07:00
..