
On the Design of Display Processors (1968) [pdf] - dedalus
http://cva.stanford.edu/classes/cs99s/papers/myer-sutherland-design-of-display-processors.pdf
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bcaa7f3a8bbc
It's covered by The Jargon File.

[http://catb.org/jargon/html/W/wheel-of-
reincarnation.html](http://catb.org/jargon/html/W/wheel-of-reincarnation.html)

> _wheel of reincarnation_

> [coined in a paper by T.H. Myer and I.E. Sutherland On the Design of Display
> Processors, Comm. ACM, Vol. 11, no. 6, June 1968)]

> Term used to refer to a well-known effect whereby function in a computing
> system family is migrated out to special-purpose peripheral hardware for
> speed, then the peripheral evolves toward more computing power as it does
> its job, then somebody notices that it is inefficient to support two
> asymmetrical processors in the architecture and folds the function back into
> the main CPU, at which point the cycle begins again.

> Several iterations of this cycle have been observed in graphics-processor
> design, and at least one or two in communications and floating-point
> processors. Also known as the Wheel of Life, the Wheel of Samsara, and other
> variations of the basic Hindu/Buddhist theological idea.

This applies to all types of coprocessors and hardware offloading. But it's
pretty funny to think that the effect is first observed in GPUs, and today the
main player is still the GPU. The history is already established, 50 years
ago.

~~~
cryptonector
In the 90s Auspex sold fileservers that had lots of specialty offload
processors. This was before modern GPUs. Then the advantage of functional
processors disappeared, and Auspex with it. Later came RDMA, which essentially
is akin to having some functional processing in NICs. Anyways. This has been
happening for a long time. But CPUs are maxed out for now, I think, so I'd
expect that the current cycle will be a long one.

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bcaa7f3a8bbc
> _But CPUs are maxed out for now, I think, so I 'd expect that the current
> cycle will be a long one._

CPUs in the future may be a mixed bag, there may be different coprocessors,
but integrated in the same physical chip - more advanced SoC. At least this
picture is what I find to be the most convincing after the end of exponential
scaling by Moore's Law.

~~~
cryptonector
Heat dissipation is an issue.

~~~
bcaa7f3a8bbc
Yes. It is already an issue of AVX2, which has the hilarious problem that the
user must try finding a net performance gain between speeding things up and
heating the CPU into thermal-throttle... But I think if an on-chip coprocessor
can offload a common task and making it more energy efficient, the thermal
issue can be avoided. We've already seen successful applications of
cryptographic instruction sets / coprocessors, video transcoding, and the
number can only get bigger.

------
Someone
_”As we have said, we know of no remote display in which the computer and
display channel are integrated into one machine, i.e. exactly one turn around
the wheel.”_

The later ZX80 was an extreme example, I think. It also supported their claim
that _”Having one processor would be cheaper”_ , but that partly was because
it was such a poor display processor.

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wbl
What's interesting is how fast the evolution is compared to the decades in the
Jargon file. The other interesting bit is how bandwidth and RAM costs would
change the architecture today.

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dang
Discussed briefly in 2014:
[https://news.ycombinator.com/item?id=7813216](https://news.ycombinator.com/item?id=7813216)

~~~
jmount
2014 poster here, happy to see it discussed again. I love the paper.

