I think it would be great to run this in moby, containerd and kubernetes CI to make sure no one expects the old thing in tests.

Isn't it why we make pre-releases for?

Apparently k8s did something about it: kubernetes/kubernetes#131059.

I would also add cri-o and podman to the list of software whose tests are potentially broken by this update.

In any case, what's done is the right thing to do, because

• practically, the rounding doesn't matter;
• over time systemd may overwrite the value we wrote using fs driver;
• there is no way to work around the systemd overwriting.

So,

• if some tests will be broken, they need to be fixed in one way or another;
• I doubt any real applications will fail, it's mostly about the tests.

In the same way we run tests on every commit and not just before releases (something that was not so uncommon decades ago), I think it makes sense to do this now. It might not need anything, or it might need fixes and it might be easy to do. But it might also point out a case we haven't really considered and we might want this to behave different in that very specific case.

Also, if changes are needed, we might be able to fix the issues now (here or in known downstream repos), so when runc is released no adjustments are needed and users can just upgrade without delay.

Fixing it now is just simpler if it's hard, and not so much extra work if there isn't anything to fix.

In the same way we run tests on every commit and not just before releases (something that was not so uncommon decades ago), I think it makes sense to do this now.

I'm sorry, I'm afraid I don't understand.

First, we don't run the tests on every commit (unfortunately it's somewhat hard to implement it on github/gha; I tried implementing it a few years ago and eventually gave up; yet I know that such setups exist, not necessarily in GHA), we only run tests on every PR.

Second, this is a PR, and therefore we do run tests on it like on every other runc PR.

Or are you saying we need to test every runc PR against kubernetes, containerd, moby, podman, cri-o etc? If that's the case, I totally agree it's a good idea in general. Yet, this is out of out of scope for this particular PR.

It might not need anything, or it might need fixes and it might be easy to do. But it might also point out a case we haven't really considered and we might want this to behave different in that very specific case.

Also, if changes are needed, we might be able to fix the issues now (here or in known downstream repos), so when runc is released no adjustments are needed and users can just upgrade without delay.

Fixing it now is just simpler if it's hard, and not so much extra work if there isn't anything to fix.

Again, if that is about testing every runc PR (and/or runc@HEAD) against its main consumers (kubernetes) etc, I do think it's a good idea, but we should discuss it separately and it should not prevent this PR from moving forward. I suggest you to open an issue for that.

I agree running every PR against those consumers is out of scope for this PR, 100% agree.

I just mean: finding bugs earlier is better, as it is easier to debug and fix. As we don't run CI against all those consumers, I think it make sense to do it manually when we see a "higher risk" of a PR affecting those consumers.

I think for this PR it can be particularly useful to test it against those consumers. I'd prefer if we can know ASAP if this breaks any of them (and if we want to change the feature slightly or just change their tests).

If you don't want to do it until we have an rc release, I don't agree it's a good idea, but it's okay too. I won't push more on this :)