How to make Firefox builds 17% faster

mmastrac•about 4 hours ago

Can you (err... buildcache) cache Rust proc-macros? I've been battling this with sccache and I'm now maintaining a 10-patch deep stack for the next.js build CI.

Windows builds were ridiculously poor on cache hits rates too because of non-determinism that was not able to figure out.

I'd be happy to test it out.

estebank•about 4 hours ago

There was an experimental PR that treats proc macros as idempotent with the corresponding colpike speed up. I don't know what happened with it, and stabilization required a lot of design work to not break backcompat. But this is something in the team's radar.

staticassertion•about 3 hours ago

Would it be possible to do somethign like editions for proc macros, or have crates establish "this is a v2 proc macro" or something? There are a lot of things I'd love to see change in a v2 but it'd all be breaking.

estebank•about 1 hour ago

Yes, I think here are workable designs.

mmastrac•about 3 hours ago

Do you have a link for this one? Would love to see it.

estebank•38 minutes ago

This is not the one I remember but another one that does part of what I'm describing.

https://github.com/rust-lang/rust/pull/145354

NooneAtAll3•about 3 hours ago

what do you mean by idempotent and colpike?

estebank•42 minutes ago

Idempotent as in if the token stream in the input doesn't change, the cached result of the previous macro expansion is used during incremental, instead of being pessimistic and rerunning the macro.

Colpike as in compile typo.

evmar•about 2 hours ago

I’m not too familiar with Firefox builds. Why are clobber builds common? At first glance it seems weird to add a cache around your build system vs fixing your build system.

jagged-chisel•about 1 hour ago

Define “fixing.” If you’re building on ephemeral containers, an external cache is necessary for files that don’t change.

allenrb•about 4 hours ago

I guess “purge 17% of the code” is not the correct answer?

K0IN•about 6 hours ago

wow, 17% is impressive with such an easy fix. i wonder if we could just build this as a separate project and pull the webidl files as a dependency.

rtpg•about 1 hour ago

managing deps as a separate project introduces a lot of day-to-day annoyances, especially if the files are actually changed decently often.

Devorlon•about 6 hours ago

Why compile code when ccache faster

amelius•about 6 hours ago

Does ccache fetch compiled code from a central server using checksums?

fishgoesblub•about 4 hours ago

buildcache, the program the post is about can use a remote server for storing the cache.

01HNNWZ0MV43FF•about 5 hours ago

sccache can, but most of us don't have access to an sccache instance: https://github.com/mozilla/sccache

firesteelrain•27 minutes ago

We use sccache on prem with MinIO.

mmastrac•about 3 hours ago

sccache is pretty easy to set up and you can back it with S3, memcache, redis, etc.

shevy-java•about 5 hours ago

So ... perhaps Mozilla should focus on user share dropping.

I understand that speed is relevant, but focusing on that strategy does not really work when dinosaur-like extinction is around the corner.

tadfisher•about 5 hours ago

I will just say this: it is unfortunate that you have chosen not to engage with the content of the article.

jeffbee•about 5 hours ago

Considering that Firefox mainly appeals to its own contributors, making the developer experience better would be important.

rebelwebmaster•about 3 hours ago

Obviously it'll make the developer more efficient to spend more time twiddling his thumbs waiting for his code to compile rather than creating a simple build performance win that allows him to, you know, spend more time improving Firefox. Not to mention all the other developers who stand to benefit from faster builds.

How to make Firefox builds 17% faster

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Discussion (23 Comments)Read Original on HackerNews