We have cryptography assembly not tested in CI for lack of amd64 SHA extensions (#69592) and more recently a potential AVX-512 failure which doesn't have CI coverage (#74767).
The C3D or C4D GCE instance types run on AMD Zen 4+, which offer SHA, AVX-512, and generally anything we might want.
The C3 or C4 instance types run Intel Sapphire Rapids, which should offer SHA and AVX-512, but maybe not SHA-512 (which we don't have assembly for yet), but reading Intel compatibility tables makes my eyes bleed so I am not sure, to be honest.
Can we update the amd64 builder instance types (or, alternatively, spin up a new longtest and maybe TryBot)?
/cc @golang/release
Comment From: mknyszek
Unfortunately, I don't think it's feasible for us to spin up C3/C3D/C4/C4D instances for the entire amd64 fleet.
We can (and should) probably do a single builder that runs in postsubmit only. (Not presubmit by default.) There are a lot of things coming down the pipeline that would benefit from an AVX-512 testing environment.
Comment From: gabyhelp
Related Issues
(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)
Comment From: gopherbot
Change https://go.dev/cl/693597 mentions this issue: main.star: add linux-amd64_avx512 builders
Comment From: mknyszek
This is done. The builder is working, and running code gated behind AVX-512 flags.
You can request it as a trybot, it's name is gotip-linux-amd64_avx512.
Comment From: Jorropo
Will it run on merged commits from time to time ?
Comment From: dmitshur
@Jorropo Yes, see the "amd64_avx512" column on the go-gotip console, for example. It's also visible on build.golang.org if you search for "avx512".