configure is slow

[woody-apple]

bootstrap takes 56 seconds, vs build takes 17
https://app.circleci.com/pipelines/github/woody-apple/connectedhomeip/159/workflows/4e720f20-aa33-48ca-baa9-84005e6664f5/jobs/846

Originally posted by @woody-apple in #631 (comment)

[gerickson]

Looking at the output, it would appear that it is the recursive configure that's the long pole here rather than bootstrap itself.

Breaking it down on my MacBook Pro, I find:

• bootstrap: 7.86s
• bootstrap -w make: 4.69s
• bootstrap -w config: 0.70s
• configure: 80.71s

[woody-apple]

Thanks! Renamed

[rwalker-apple]

@woody-apple is bootstrap.sh in the run referenced above using configure -C?

[rwalker-apple]

nevermind. got it

[woody-apple]

Pre Run: https://app.circleci.com/pipelines/github/woody-apple/connectedhomeip/162/workflows/7e79feb7-5fd7-432a-8b62-6ffe557a640b/jobs/878

Post Run: https://app.circleci.com/pipelines/github/woody-apple/connectedhomeip/163/workflows/0c6d56a0-35bf-4a16-a62c-4f94bd2ceaa9/jobs/885

It's 20seconds faster, but still a minute for the 'bootstrap' phase. Any more things we can pull here?

[woody-apple]

@rwalker-apple

[woody-apple]

This also actually breaks the build:
https://app.circleci.com/pipelines/github/woody-apple/connectedhomeip/163/workflows/0c6d56a0-35bf-4a16-a62c-4f94bd2ceaa9/jobs/892

[rwalker-apple]

next biggest chunk of optimization of configure would come from taking nlfriends out of the tree, making them an external dependency like openssl

this would also remove nlfriends from make distcheck, make coverage, and it would also mean that customers of CHIP would need to go get them (a la openssl)

[turon]

I agree that running configure of each of the nlfriends is taking the majority of time. And for nlfriends such as nlassert and nlio, which primarily just provide headers (outside of unit tests), this time seems especially wasteful.

In a cmake prototype I've been experimenting with, simply hooking in configure of third_party/nlfriends increased initial build time from ~2s to >20s.