8 ms·

Transputers weren't dataflow. They were parallel processors. The Transputer had a program counter (instruction pointer). Dataflow machines don't need one:

Transputers weren't dataflow. They were parallel processors. The Transputer had a program counter (instruction pointer). Dataflow machines don't need one: when an instruction has all of its inputs, it executes on the next available processor. Only a few experimental dataflow machines were ever built, e.g. the one at Manchester University.

duelingjello 7y ago
MIT Tagged Token machine is another TTDA. I actually wonder if cheaper CAM or Qubits would help, even though debugging would still be very, very painful.
greglindahl 7y ago
Check out https://en.wikipedia.org/wiki/Dataflow_programming https://en.wikipedia.org/wiki/Dataflow_programming -- the word means a lot more than you've mentioned.
- dboreham 7y ago
  You could program a dataflow system on a network of Transputers but the hardware isn't dataflow. We would have called it a General Purpose Parallel machine.
- resoluteteeth 7y ago
  They're talking about https://en.wikipedia.org/wiki/Dataflow_architecture https://en.wikipedia.org/wiki/Dataflow_architecture not dataflow programming.
  - greglindahl 7y ago
    The two are related. The Wikipedia article I posted has appropriate links that explain the relationship. Note that I replied to someone who said “dataflow“ and not dataflow hardware or architecture.
    - resoluteteeth 7y ago
      > Note that I replied to someone who said “dataflow“ and not dataflow hardware or architecture. The comment you directly replied to, yes, but it was itself responding to a comment saying "they are the closest to a dataflow... processor" which seems to be referring to dataflow architecture?
- DonaldFisk 7y ago
  I've been developing a dataflow programming language, which runs on a tagged dataflow virtual machine: http://www.fmjlang.co.uk/fmj/tutorials/TOC.html http://www.fmjlang.co.uk/fmj/tutorials/TOC.html I'll update the link soon, as I've added several new features to the language.
  - greglindahl 7y ago
    I've worked on a ton of dataflow systems which were macro-dataflow, i.e. they executed on conventional processors. Great programming model in many instances.
  - dang 7y ago
    Please do!
  - zepto 7y ago
    Good name
nine_k 7y ago
What is the key difference of transputers and GPUs / vector processors? Is PS3 with several Cells somehow reminiscent of a transputer?
- m463 7y ago
  GPUs use SIMT or similar, where there are several parallel threads with a shared program counter.
- djd20 7y ago
  Yes - there where a number of commonalities and some research was done into running Occam (a language co-designed with the transputer) on the cell by means of a transputer VM: http://www.transterpreter.org/publications/pdfs/a-cell-transterpreter.pdf http://www.transterpreter.org/publications/pdfs/a-cell-trans... Fun times :)
  - gnufx 7y ago
    For what it's worth, the FPS T machine attached processors used transputers plus vector units.
jacquesm 7y ago
Technically true, which is probably the best kind of true, but if we're going to get technical I did say closest. You could program a Transputer to use its links as inputs and outputs in a fabric where the implementation details of program counters and firmware running on a particular Transputer were hidden from sight. This allowed for all kind of interesting architectures to be created 'ad hoc' without having to go through the stages of circuit design and so on, and it allowed for much more complex operations than you'd be able to get out of a 'real' dataflow processor on a single tick or message passed from one processor to another because of the much higher level at which they operated. So sure, they weren't true dataflow processors right off the bat but you could make them look like a pretty good simulation of one on the outside, even if you didn't have access to a crossbar switch (which would be cheating) and absent the real thing that was as close as I was going to get at the time.
- namibj 7y ago
  Running something like https://github.com/TimelyDataflow/timely-dataflow https://github.com/TimelyDataflow/timely-dataflow on a transputer fabric might be how general purpose computing could interface with this sort of hardware.
gnufx 7y ago
The Maxeler hardware claims to be dataflow, and there is some in these parts. However, I couldn't find out much about it except that it doesn't seem to support languages with a Lucid/SISAL-type heritage.

duelingjello 7y ago

MIT Tagged Token machine is another TTDA. I actually wonder if cheaper CAM or Qubits would help, even though debugging would still be very, very painful.

greglindahl 7y ago

Check out https://en.wikipedia.org/wiki/Dataflow_programming https://en.wikipedia.org/wiki/Dataflow_programming -- the word means a lot more than you've mentioned.

dboreham 7y ago
You could program a dataflow system on a network of Transputers but the hardware isn't dataflow. We would have called it a General Purpose Parallel machine.
resoluteteeth 7y ago
They're talking about https://en.wikipedia.org/wiki/Dataflow_architecture https://en.wikipedia.org/wiki/Dataflow_architecture not dataflow programming.
- greglindahl 7y ago
  The two are related. The Wikipedia article I posted has appropriate links that explain the relationship. Note that I replied to someone who said “dataflow“ and not dataflow hardware or architecture.
  - resoluteteeth 7y ago
    > Note that I replied to someone who said “dataflow“ and not dataflow hardware or architecture. The comment you directly replied to, yes, but it was itself responding to a comment saying "they are the closest to a dataflow... processor" which seems to be referring to dataflow architecture?
DonaldFisk 7y ago
I've been developing a dataflow programming language, which runs on a tagged dataflow virtual machine: http://www.fmjlang.co.uk/fmj/tutorials/TOC.html http://www.fmjlang.co.uk/fmj/tutorials/TOC.html I'll update the link soon, as I've added several new features to the language.
- greglindahl 7y ago
  I've worked on a ton of dataflow systems which were macro-dataflow, i.e. they executed on conventional processors. Great programming model in many instances.
- dang 7y ago
  Please do!
- zepto 7y ago
  Good name

nine_k 7y ago

What is the key difference of transputers and GPUs / vector processors? Is PS3 with several Cells somehow reminiscent of a transputer?

m463 7y ago
GPUs use SIMT or similar, where there are several parallel threads with a shared program counter.
djd20 7y ago
Yes - there where a number of commonalities and some research was done into running Occam (a language co-designed with the transputer) on the cell by means of a transputer VM: http://www.transterpreter.org/publications/pdfs/a-cell-transterpreter.pdf http://www.transterpreter.org/publications/pdfs/a-cell-trans... Fun times :)
- gnufx 7y ago
  For what it's worth, the FPS T machine attached processors used transputers plus vector units.

jacquesm 7y ago

Technically true, which is probably the best kind of true, but if we're going to get technical I did say closest. You could program a Transputer to use its links as inputs and outputs in a fabric where the implementation details of program counters and firmware running on a particular Transputer were hidden from sight. This allowed for all kind of interesting architectures to be created 'ad hoc' without having to go through the stages of circuit design and so on, and it allowed for much more complex operations than you'd be able to get out of a 'real' dataflow processor on a single tick or message passed from one processor to another because of the much higher level at which they operated. So sure, they weren't true dataflow processors right off the bat but you could make them look like a pretty good simulation of one on the outside, even if you didn't have access to a crossbar switch (which would be cheating) and absent the real thing that was as close as I was going to get at the time.

namibj 7y ago
Running something like https://github.com/TimelyDataflow/timely-dataflow https://github.com/TimelyDataflow/timely-dataflow on a transputer fabric might be how general purpose computing could interface with this sort of hardware.

gnufx 7y ago

The Maxeler hardware claims to be dataflow, and there is some in these parts. However, I couldn't find out much about it except that it doesn't seem to support languages with a Lucid/SISAL-type heritage.