EICrecon takes 20 minutes to build

[veprbl]

time cmake --build build -- -j1

real    22m48.523s
user    21m30.882s
sys     1m0.390s

[veprbl]

An output of compiling with -DCMAKE_CXX_COMPILER_LAUNCHER=time -DCMAKE_CXX_LINKER_LAUNCHER=time suggests that the time spent linking is negligible.

[veprbl]

Also, apparently, it's not related to datamodel_glue.h or datamodel_includes.h.

[nathanwbrei]

I've heard that clang has some nifty compile-time profiling tools, though I haven't tried them out yet. I'd be interested in how you profile this. Or maybe I should figure it out.

[veprbl]

I've heard that clang has some nifty compile-time profiling tools, though I haven't tried them out yet.

Glad that you've posted this sentence. I wasn't able to figure out how to ask google about this. -ftime-trace looks promising.

[veprbl]

Looking at few files, Eigen is a big offender, but that's what it does. There are some "spdlog" and "JANA" headers that don't take much time (~1s?), but they should add up over the codebase. It came to me as a surprise, but a lot of time is spent in the "backend" (even for a -DCMAKE_BUILD_TYPE= build).

[veprbl]

I've tried using include-what-you-use (IWYU), and it gave me about 1-2 minutes speedup (5%). Not much, given that it requires quite a bit of tuning to get a nice and working diff.

[veprbl]

Sorry, not sure what happened. I didn't mean to forcefully assign anyone.

[nathanwbrei]

No worries! I just assumed you gave up in frustration and were hoping I'd think of something