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chasil 3 hours ago

Bob Colwell mentions originally doing out of order design at Multiflow.

He was a key player in the Pentium Pro out of order implementation.

https://www.sigmicro.org/media/oralhistories/colwell.pdf

"We should also say that the 360/91 from IBM in the 1960s was also out of order, it was the first one and it was not academic, that was a real machine. Incidentally that is one of the reasons that we picked certain terms that we used for the insides of the P6, like the reservation station that came straight out of the 360/91."

Here is his Itanium commentary:

"Anyway this chip architect guy is standing up in front of this group promising the moon and stars. And I finally put my hand up and said I just could not see how you're proposing to get to those kind of performance levels. And he said well we've got a simulation, and I thought Ah, ok. That shut me up for a little bit, but then something occurred to me and I interrupted him again. I said, wait I am sorry to derail this meeting. But how would you use a simulator if you don't have a compiler? He said, well that's true we don't have a compiler yet, so I hand assembled my simulations. I asked "How did you do thousands of line of code that way?" He said “No, I did 30 lines of code”. Flabbergasted, I said, "You're predicting the entire future of this architecture on 30 lines of hand generated code?" [chuckle], I said it just like that, I did not mean to be insulting but I was just thunderstruck. Andy Grove piped up and said "we are not here right now to reconsider the future of this effort, so let’s move on"."