Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.prolog > #15075

Nope, you can't, because of the CRCW instuction (Was: parallel random-access machine)

Cross-posted to 3 groups.

Show all headers | View raw

Hi,

Simulation is not so easy. You would need an
element of non-determinism, or if you want
call it randomness. Because PRAM has this

instructions, ERCW, CRCW, etc..

- Concurrent read concurrent write (CRCW)—
multiple processors can read and write. A
CRCW PRAM is sometimes called a concurrent
random-access machine.
https://en.wikipedia.org/wiki/Parallel_RAM

Modelling via von Neuman what happens there
can be quite challenging. At least it doesn't
allow for a direct modelling.

What a later processor sees, depends extremly
on the timing and which processor "wins" the
write.

Also I don't know what it would buy you
intellectually to simulate a PRAM on a random
von Neuman machine. The random von Neuman

machine could need more steps than the PRAM
in summary, because it has to simulate a PRAM.
But I guess its the intellectual questioning

that needs also a revision when confronted
with the new architecture of unified memory
and tensor processing cores.

Bye

Maciej Woźniak schrieb:
> On 12/1/2025 12:15 PM, Mild Shock wrote:
>> Hi,
>>
>> You wrote:
>>
>>  > No, they don't, they just add one (or some)
>>  > more layer on top of it.
>>
>> Techically they are not von Neuman architecture.
>> Unified Memory with Multiple Tensor Cores is
>> not von Neuman architecture. 
> 
> We can use von Neumann architecture
> to emulate other architectures, but as long as it
> is performed by our computers it is technically
> von Neumann's.
> 

Back to comp.lang.prolog | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

What is analog computing nowadays? (Re: An old Busy Beaver ASIC (Application-Specific Integrated Circuit) (Was: Could AlphaEvolve find the sixth busy beaver ?) Mild Shock <janburse@fastmail.fm> - 2025-12-01 11:25 +0100
  Wake-up call until everybody gets ear-bleeding (Re: What is analog computing nowadays?) Mild Shock <janburse@fastmail.fm> - 2025-12-01 12:01 +0100
    BB(745) is independent of ZFC (Was: Wake-up call until everybody gets ear-bleeding) Mild Shock <janburse@fastmail.fm> - 2025-12-01 12:07 +0100
      Write ZFC formulas on a tape (of a Turing machine) (Re: BB(745) is independent of ZFC ) Mild Shock <janburse@fastmail.fm> - 2025-12-02 17:18 +0100
        Turing machines have neurons (Re: Write ZFC formulas on a tape (of a Turing machine)) Mild Shock <janburse@fastmail.fm> - 2025-12-02 17:19 +0100
          A logical calculus in nervous activity [McCulloch & Pitts 1943] (Re: Turing machines have neurons) Mild Shock <janburse@fastmail.fm> - 2025-12-02 17:20 +0100
            Busy Beaver and Theory Consistency (Was: A logical calculus in nervous activity [McCulloch & Pitts 1943]) Mild Shock <janburse@fastmail.fm> - 2025-12-02 17:39 +0100
            Busy Beaver and Theory Consistency (Was: A logical calculus in nervous activity [McCulloch & Pitts 1943]) Mild Shock <janburse@fastmail.fm> - 2025-12-02 17:43 +0100
              Re: Busy Beaver and Theory Consistency (Was: A logical calculus in nervous activity [McCulloch & Pitts 1943]) Mild Shock <janburse@fastmail.fm> - 2025-12-02 23:18 +0100
  Re: What is analog computing nowadays? (Re: An old Busy Beaver ASIC (Application-Specific Integrated Circuit) (Was: Could AlphaEvolve find the sixth busy beaver ?) Maciej Woźniak <mlwozniak@wp.pl> - 2025-12-01 12:09 +0100
    parallel random-access machine (parallel RAM or PRAM (Was: What is analog computing nowadays?) Mild Shock <janburse@fastmail.fm> - 2025-12-01 12:15 +0100
      Re: parallel random-access machine (parallel RAM or PRAM (Was: What is analog computing nowadays?) Maciej Woźniak <mlwozniak@wp.pl> - 2025-12-01 13:23 +0100
        Nope, you can't, because of the CRCW instuction (Was: parallel random-access machine) Mild Shock <janburse@fastmail.fm> - 2025-12-01 17:12 +0100
          Algorithm introduced in Hogwild! SGD (Niu et al., 2011) (Was: Nope, you can't, because of the CRCW instuction) Mild Shock <janburse@fastmail.fm> - 2025-12-01 17:31 +0100
            PRAMs might be closer to physics: Boltzman machines, etc.. (Was: Algorithm introduced in Hogwild! SGD) Mild Shock <janburse@fastmail.fm> - 2025-12-01 18:02 +0100
          Re: Nope, you can't, because of the CRCW instuction (Was: parallel random-access machine) Maciej Woźniak <mlwozniak@wp.pl> - 2025-12-01 17:59 +0100
            PRAMs might be closer to physics: Boltzman machines, etc.. (Re: Nope, you can't, because of the CRCW instuction) Mild Shock <janburse@fastmail.fm> - 2025-12-01 18:05 +0100
            PRAMs might be closer to physics: Boltzman machines, etc.. (Re: Nope, you can't, because of the CRCW instuction) Mild Shock <janburse@fastmail.fm> - 2025-12-01 18:08 +0100
              Physics more difficult than Rasperry LED cube? (Was: PRAMs might be closer to physics: Boltzman machines, etc..) Mild Shock <janburse@fastmail.fm> - 2025-12-01 18:25 +0100
        Re: parallel random-access machine (parallel RAM or PRAM (Was: What is analog computing nowadays?) Thomas Heger <ttt_heg@web.de> - 2025-12-03 07:17 +0100
          Re: parallel random-access machine (parallel RAM or PRAM (Was: What is  analog computing nowadays?) Python <python@cccp.invalid> - 2025-12-03 06:46 +0000
          Re: parallel random-access machine (parallel RAM or PRAM) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2025-12-03 08:02 +0100
      Linux kernel's RCU-protected hash tables (Re: Algorithm introduced in Hogwild! SGD (Niu et al., 2011)) Mild Shock <janburse@fastmail.fm> - 2025-12-01 22:26 +0100
        String interning is HashSet and not HashMap (Was: Linux kernel's RCU-protected hash tables) Mild Shock <janburse@fastmail.fm> - 2025-12-01 22:40 +0100
      POINT OF VIEW OF AN ALGORITHM (Re: Algorithm introduced in Hogwild! SGD (Niu et al., 2011)) (Re: parallel random-access machine) Mild Shock <janburse@fastmail.fm> - 2025-12-01 23:12 +0100
        Introduction to AMBA® 4 ACE™ (2011) (Was: POINT OF VIEW OF AN ALGORITHM) Mild Shock <janburse@fastmail.fm> - 2025-12-01 23:37 +0100
          Sputnik Schock: Academia is Disposable [I. J. Good Ultraintelligence] (Was: Introduction to AMBA® 4 ACE™ (2011)) Mild Shock <janburse@fastmail.fm> - 2025-12-01 23:53 +0100

csiph-web