Is anyone aware of any attempt to compare rustc's overall performance over (say) the last year? I know @nnethercote has had a series of awesome posts on this, I'd be curious to try and do a more "overall" comparison (if I recall, their posts were fairly fine-grained)
I guess I ought to be able to get this data from perf
forgot about that
that should still work, right?
yep, that is indeed precisely what it was for
doesn't go that far back
also heh doens't look too impressive :)
but I guess them's the breaks
it doesn't seem to be up-to-date though
I mean the ratio between incremental / the rest is good
maybe @simulacrum can update it?
@mw do you happen to know what was the 1.23 -> 1.24 transition?
I think that was when we turned on incremental compilation on stable
That wasn't ThinLTO?
and parallel codegen?
yes, as @Wesley Wiser says
I think, at least
For example, another change related to performance hit stable this release: codegen-units is now set to 16 by default.
so, default parallel codegen for opt builds, which was enabled by thinlto
Ah, forgot to push the 1.30 data
should be up to date now
incremental opt builds "seem" to have regressed from 1.30 onwards
that is not really the case. before they were building without ThinLTO
now they use ThinLTO by default, so the resulting binaries should be a lot faster
sadly, not a single person wanted to give it a try :) :'(
which makes me think that people say that they care about Rust compile times because they are just used to doing so :P
Well part of it is I think generally "too slow" -- I personally only really notice it when working on librustc or librustc_mir especially after a rebase with >200s compiletimes IIRC
@nikomatsakis we build libc with a bunch of different compilers on CI, these are super coarse results and libc is not a very interesting library: Screen-Shot-2019-02-26-at-09.17.27.png
the current stable build is at 8:39 mins, so from Rust 1.13 with 9:05 until the last stable, the progress doesn't look to be huge
some 1.20 build appears to be at 7:41, and worst was 1.24 with ~10:00
so if anything it feels like Rust has been able to add more features without making compile times worse, but it does not feel like compile-times have been reduced significantly
or at least not from these results
those builds do a lot more stuff than just compiling Rust though
(use rustup to add targets which requires downloading, etc.)
so the differences might just be some CI bot got lucky while downloading something