so why /does/ compiling llvm on 12 3.5 GHz cores take an hour and a half?

@tindall probably really bad compilation unit fragmentation/bottlenecking and weird code patterns that the optimizer chokes on? idk

@tindall huh, no idea. Actually, ignore me; I'm thinking of llvm-in-rust builds, not standalone llvm.

@tindall well it’s gotta wait for itself to compile first to start compiling, obvs

@tindall that's ... really something. Last time I compiled it (on an 8 core/16 thread box, ~4ghz) it took about 16 minutes – including running some of the tests afterwards.
It sounds like it wasn't using all your cpu cores, what did you specify as the "-j" option when running make?

@kepstin well, all my cores were at 100 percent, so I think it was.

Sign in to participate in the conversation

Cybrespace is an instance of Mastodon, a social network based on open web protocols and free, open-source software. It is decentralized like e-mail.