Recent submissions

Comment · 1 year ago
If someone tries to run your method but messes it up, and then accuses you of fraud when the results don't match their expectations, I'm not sure they're entitled to a neutral tone in response.

Maybe you're right, and a more neutral tone would have been effective! I think it's just that Jeff is just really done with this.

Comment · 1 year ago
I think the pre-trained checkpoint uses the same 20 TPU blocks as the original paper, but it probably isn't the exact-same checkpoint, as the paper itself is from 2020/2021.
Comment · 1 year ago
As Andrew Kahng was one of the co-authors of Cheng et al., all of the issues with his reproduction still matter here. The Nature paper went through an investigation and second round of peer review.

AlphaChip is used to make real chips in production. Google publicly announced its use in multiple generations of TPUs and Axion CPUs, and MediaTek said they've built on it as well.

Comment · 1 year ago
Three generations of TPU, Axion (ARM-based CPU), various other chips at AlphaBet, MediaTek's usage...
Comment · 1 year ago
The UCSD paper didn't run the Nature method correctly, so I don't see how you can draw this conclusion.

From Jeff's tweet:

"In particular the authors did no pre-training (despite pre-training being mentioned 37 times in our Nature article), robbing our learning-based method of its ability to learn from other chip designs, then used 20X less compute and did not train to convergence, preventing our method from fully learning even on the chip design being placed."

As for Chatterjee's paper, "We provided the committee with one-line scripts that generated significantly better RL results than those reported in Markov et al., outperforming their “stronger” simulated annealing baseline. We still do not know how Markov and his collaborators produced the numbers in their paper."

Comment · 1 year ago
"Prior to publication of Cheng et al., our last correspondence with any of its authors was in August of 2022 when we reached out to share our new contact information."

You don't stop being the corresponding authors of a paper when you change companies, and whatever "unclear circumstances" you imagine took place when they left, they were also re-hired later, which a company would only do if they were in good standing.

In any case, those "Google contacts" also expressed concerns with how Cheng et al. were doing their study, which they ignored:

3.4 Cheng et al.’s Incorrect Claim of Validation by Google Engineers

Cheng et al. claimed that Google engineers confirmed its technical correctness, but this is untrue. Google engineers (who were not corresponding authors of the Nature paper) merely confirmed that they were able to train from scratch (i.e. no pre-training) on a single test case from the quick start guide in our open-source repository. The quick start guide is of course not a description of how to fully replicate the methodology described in our Nature paper, and is only intended as a first step to confirm that the needed software is installed, that the code has compiled, and that it can successfully run on a single simple test case (Ariane).

In fact, these Google engineers share our concerns and provided constructive feedback, which was not addressed. For example, prior to publication of Cheng et al., through written communication and in several meetings, they raised concerns about the study, including the use of drastically less compute, and failing to tune proxy cost weights to account for a drastically different technology node size.

The Acknowledgements section of Cheng et al. also lists the Nature corresponding authors and implies that they were consulted or even involved, but this is not the case. In fact, the corresponding authors only became aware of this paper after its publication.

Comment · 1 year ago
"These major methodological differences unfortunately invalidate Cheng et al.’s comparisons with and conclusions about our method. If Cheng et al. had reached out to the corresponding authors of the Nature paper[8], we would have gladly helped them to correct these issues prior to publication[9].

[8] Prior to publication of Cheng et al., our last correspondence with any of its authors was in August of 2022 when we reached out to share our new contact information.

[9] In contrast, prior to publishing in Nature, we corresponded extensively with Andrew Kahng, senior author of Cheng et al. and of the prior state of the art (RePlAce), to ensure that we were using the appropriate settings for RePlAce."

Comment · 1 year ago
I mean, I think second is still "one of the first?" And, no offense to this project, but I don't know of it being used in a real industrial setting, whereas AlphaChip was used in TPU.
Comment · 1 year ago
Comment · 1 year ago
> Does the EDA ecosystem support a similarly open culture of benchmarking for commercial tools?

If only. The comparison in Cheng et al. is the only public comparison with CMP that I can recall, and it is pretty suss that this just so happens to be a very pro-commercial-autoplacer study. (And, Cheng et al. have cited 'licensing agreements' as a reason for not giving out the synthesized netlists necessary to reproduce their results.)

Reminded a bit of Oracle. They likewise used to (and maybe still?) prohibit any benchmarking of their database software against that of another provider. This seems to be a common move for solidifying a strong market position.

Comment · 1 year ago
> Did they mess up when they did not pre-train or they followed the "steps" described in the original repo and tried to get a fair reproduction?

The Circuit Training repo was just going through an example. It is common for an open-source repo to describe simple examples for testing / validating your setup --- that does not mean this is how you should get optimal results in general. The confusion may stem from their statement that, in this example, they produced results that were comparable with the pre-trained results in the paper. This is clearly not a general repudiation of pre-training.

If Cheng et al. genuinely felt this was ambiguous, they should have reached out to the corresponding authors. If they ran into some part of the repo they felt they had to "reverse-engineer", they should have asked about that, too.

Comment · 1 year ago
Comment · 1 year ago
Are you really suggesting that the TPU team does not stand behind the graphs in Google's own blog post? And that MediaTek does not stand behind their quoted statement?
Comment · 1 year ago
His original complaint being dismissed matters because it suggests that he was fishing around for a complaint that was valid, and that perhaps his primary motivation was to get money out of Google.

Legal nitpick - you can get away with alleging pretty much whatever you want in a legal complaint. You can't even be sued for defamation if it turns out later you were lying.

Jeff Dean isn't saying that Cheng et al. should be unpublished; he's saying that they didn't run the method the same way. It is perfectly fine for someone to try changing the method and report what they found. What's not fine is to claim that this means that Google was lying in their study.

Comment · 1 year ago

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