Hi all,
We're looking into reducing our build time.
The first benchmark we did was to measure build time of aosp_arm64 versus number of parallel jobs.
We have a machine with 28 cores (56 threads), so i ran a script to build aosp from 4 jobs up to 56 jobs with an increment of 4.
The results surprised me, in a nutshell, with ccache enabled and 100% hit rate
4 cores: 1h
8 cores: 42m
12 cores: 35m
16+ cores: 32m
Throwing more than 16 cores doesn't influence build time anymore, the curve is flat!
I just can't explain what is going on here. Does anyone know why the build process doesn't scale?
I'm currently running the same benchmark with ccache disabled. Will post an update once i have the data.
Anyone knows how to disable some of the build tasks? For example i've noticed that there is a lot of java source processing and wonder if they are all needed. I'm pretty sure that some documentation is generated, in our case we don't need that.
As well, any tips or feedback around reducing build times would be more than welcome.
Thanks,
Chris