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Comment by Drunk_Engineer | Hacker News Reader

I have not read the latest paper, but their previous work was really unclear about metrics being used. Researchers trying to replicate results had a hard time getting reliable details/benchmarks out of Google. Also, my recollection is that Google did not even compute timing, just wirelength and congestion; i.e. extremely primitive metrics.

Floorplanning/placement/synthesis is a billion dollar industry, so if their approach were really revolutionary they would be selling the technology, not wasting their time writing blog posts about it.

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Like when Google wasted its time writing publicly about Spanner?

https://research.google/pubs/spanner-googles-globally-distri...

or Bigtable?

https://research.google/pubs/bigtable-a-distributed-storage-...

or GFS?

or MapReduce?

or Borg?

or...I think you get the idea.

Spanner research paper was in 2012. Bigtable was in 2006. GFS 2003. The last decade has been a 'lost decade' of google. Not much innovation to be honest.

Attention is all you need is 2017... https://arxiv.org/abs/1706.03762

They thought it was dead end, that is why they released it :P

I am not sure these publications were intended to generate sales of these technologies. My assumption is that they mostly help the company in terms of recruitment. This lets potential employees see cool stuff Google is doing, and see them as an industry leader.

Spanner is literally a Google cloud product you can buy ignoring that it underpins a good amount of Google tech internally. The same is true of other stuff. Dismissing it as a recruitment tool indicates you haven’t worked at Google or really know much about their product lines.

He didn't say that Spanner is only a recruitment tool but that the blog posts about Spanner (and other core technologies of Google) might be.

More people see the blog posts as it’s a more gentle introduction than the paper itself. Sure it might generate interest in Google but it also generates interest for people to further look into the research. They are not for sales of the tech but I’m not sure the impact is just a recruitment tool even if that’s how Google justified the work to itself.

> Floorplanning/placement/synthesis is a billion dollar industry

Maybe all together, but I don't think automatic placement algorithms are a billion dollar industry. There's so much more to it than that.

Yes in combination. Customers generally buy these tools as a package deal. If the placer/floorplanner blows everything else out of the water, then a CAD vendor can upsell a lot of related tools.

The original paper reports P&R metrics (WNS, TNS, area, power, wirelength, horizontal congestion, vertical congestion) - https://www.nature.com/articles/s41586-021-03544-w

(no paywall): https://www.cl.cam.ac.uk/~ey204/teaching/ACS/R244_2021_2022/...

From what I saw in the rebuttal papers, the Google cost-function is wirelength based. You can still get good TNS from that if your timing is very simplistic -- or if you choose your benchmark carefully.

They optimize using a fast heuristic based on wirelength, congestion, and density, but they evaluate with full P&R. It is definitely interesting that they get good timing without explicitly including it in their reward function!

Yeah; it means the heuristic they use is a good one

Interesting == Suspicious? I think this is a big red flag to those in the know.

The odd thing is that they don't compute timing in RL, but claim that somehow TNS and WNS improved. Does anyone believe this? With five circuits and three wins, the results are a coin toss.

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