look into C++ build throughput

The C++ team put out this blog post with information related to tuning up your build... could be something for us to investigate? https://devblogs.microsoft.com/cppblog/cpp-build-throughput-investigation-and-tune-up/

Start with the linked C++ build throughput investigation and determine which build configuration or workflow in this repository should be measured. The issue names no files, tests, or entry points, so first establish a reproducible baseline and define the target improvement. Done requires an agreed scope, measurable throughput results, and identified changes.

Written by the indexing model from the issue text.