Startup time of 1000 packages – 53% slower in Julia 1.12 vs 1.10

[roflmaostc]

@Datseris

This triggers precompilation surprisingly frequently for reasons I never fully understood (so far I thought that once a package is precompiled it stays as such forever even if you later precompile a newer version, but I guess that’s not the case?).

Same, it seems to be very unpredictable sometimes.
However, one reason could be that Julia only stores 10 different precompilation files for a package by default. In my case, I set export JULIA_MAX_NUM_PRECOMPILE_FILES=50 to have more files stored.

Also shameless plug: I assembled PrecompileAfterUpdate.jl which avoids the unexpected precompilation after Julia updates. It crawls through your recent manifests and precompiles then whenever you want (for example after a Julia update)