Dan Ingalls talks about Notetaker/Smalltalk-78 in his forthcoming HOPL 4 paper which should be available within the next two weeks.
There were only a few Notetaker machines built and apparently they were quite slow and not really very useful. But the Notetaker image and VM was also ported to the Dorado. In 1979-80 that was the primary version that was being used within the LRG and was used as the starting point for creating Smalltalk-80.
In my article is a link to the the invitation letter to Tektronix to participate in the Smalltalk-80 dissemination processed. In it they said: "We estimate about one work year for a very expert systems programmer to implement the microcode for the virtual machine and implement the i/o primitives." In the following discussions and visits they only showed us and talked about the microcoded Dorado and Dolphin implementations. They we repeated said words to the effect of "We want you to design a computer to run Smalltalk". LRG was quite secretive about some things and I don't think I had ever heard of Notetaker until 1993 when I read Alan's HOPL-2 paper.
One interesting thing I recently learned from Dan was that NoteTaker used a linear stack with overlapping activation records. This was dropped for the Dorado implementation and Smalltalk-80. That was unfortunate as the overhead of heap allocated stack frames was one of the major performance bottlenecks when implementing Smalltalk-80 on conventional processors. It took those of us doing such implementations a couple years to develop techniques for "cheating without getting caught" while using hidden linear stacks. In retrospect, the poor performance of Smalltalk-80's heap allocated activation contexts in combination with reference counting significantly delayed the viability of microprocessor based Smalltalk-80 implementations.
Interestingly, the 2nd argument to Object.create was specifically designed (by me) so that an object's "shape" could be statically determined. If the descriptor is all literals (they usually are) then each Object.create call site is essentially a construction site for a "class" of objects that share a common structure.
As Erik says, this should be fixable. It sounds to me like Crock's coding style is just ahead of the engine implementation curve. Hopefully it will help push this optimization into the actual implementations.
There were only a few Notetaker machines built and apparently they were quite slow and not really very useful. But the Notetaker image and VM was also ported to the Dorado. In 1979-80 that was the primary version that was being used within the LRG and was used as the starting point for creating Smalltalk-80.
In my article is a link to the the invitation letter to Tektronix to participate in the Smalltalk-80 dissemination processed. In it they said: "We estimate about one work year for a very expert systems programmer to implement the microcode for the virtual machine and implement the i/o primitives." In the following discussions and visits they only showed us and talked about the microcoded Dorado and Dolphin implementations. They we repeated said words to the effect of "We want you to design a computer to run Smalltalk". LRG was quite secretive about some things and I don't think I had ever heard of Notetaker until 1993 when I read Alan's HOPL-2 paper.
One interesting thing I recently learned from Dan was that NoteTaker used a linear stack with overlapping activation records. This was dropped for the Dorado implementation and Smalltalk-80. That was unfortunate as the overhead of heap allocated stack frames was one of the major performance bottlenecks when implementing Smalltalk-80 on conventional processors. It took those of us doing such implementations a couple years to develop techniques for "cheating without getting caught" while using hidden linear stacks. In retrospect, the poor performance of Smalltalk-80's heap allocated activation contexts in combination with reference counting significantly delayed the viability of microprocessor based Smalltalk-80 implementations.