[davep]

$this->bbcode_second_pass_quote('', 'I') am still waiting for you techtopians to...

[Outcast_Searcher]

$this->bbcode_second_pass_quote('ennui2', '')$this->bbcode_second_pass_quote('pstarr', 'I') am still waiting for you techtopians to project implementation of true natural language processing. Come back to me when Siri can parse this simple string; Time flies like an arrow. into it various permutations.

[ennui2]

$this->bbcode_second_pass_quote('pstarr', '
')I never said computers don't matter.

[davep]

$this->bbcode_second_pass_quote('pstarr', '')$this->bbcode_second_pass_quote('ennui2', 'B')ut it's not going to necessarily flat-line how and when you'd like it to. There are still some interesting things going on. The vast majority of Graeme's revolutionary-sounding breakthroughs won't amount to anything, but a few probably will.

[lpetrich]

It looks like we have reached the limit of the feasible size of an integrated-circuit component. This means that computer-chip design will have to expand in other directions. Instead of vertical expansion (faster, smaller components), we will have lots of horizontal expansion (more components).

This produces a serious programming challenge. With more components per chip and individual processors having the same number of components, a logical route of expansion is more individual processors. This means that one can do more parallel processing per chip.

Each individual processor is a single-instruction-stream, single-data-stream (SISD) system, the sort of thing that one learns early in a computer-architecture class.

For multiple processors, one can make them act like separate individual ones, making a multiple-instruction-stream, multiple-data-stream (MIMD) system. This is the most flexible approach, but also the most complicated one.

One can use the shortcut of having several processors do the same instructions, while operating on different sets of data. This gives a single-instruction-stream, multiple-data-stream (SIMD) system.

In practice, the two are often combined.

Intel has supported SIMD in its x86 chips since the mid-1990's: MMX, SSE, AVX. These chips issue SIMD instructions alongside their SISD ones. This is also done in some other chip architectures, like POWER/PowerPC, Sparc, MIPS, ARM, and PA-RISC.

Multicore chips are essentially MIMD, with each core being SISD though often with SIMD as explained above.

GPU's often use SIMD, for reasons that ought to be obvious -- doing the same thing to lots of pixels.

[lpetrich]

SIMD and MIMD architectures have lots of programming challenges.

MIMD is the easiest to program for. Programming for it is an extension of programming for multitasking and multithreading in general, programming that has been done for some decades now, long before MIMD systems became common. It is done because it is a great convenience for many applications, like supporting multiple users and multiple active apps and multiple Internet-client requests. Going from SISD to MIMD only requires some changes to OS kernels, for distributing tasks and threads among several CPU cores.

SIMD is more difficult to program for. It is designed for problems where one does the same calculations on different sets of data, like rendering operations for different pixels in an image. Arithmetic and logical operations are straightforward for it, but its big difficulty is flow of control. For if-then-else statements, a common approach is to calculate both branches for each stream of data, then calculate a condition flag for each stream of data, then select which of the branches for each stream using its condition-flag value. Loops are even worse. Fixed numbers of loops are no problem, but if one wants to exit from a loop, there is the problem that different streams may want to exit after different numbers of loopings.

So in practice, SIMD processing is implemented as "slaves" of SISD or MIMD "masters".

I think that we will be seeing more of SIMD processing, since that is a good way of doing some AI operations, like artificial-vision ones.

[aadbrd]

Sorry for the thread bump but this was timely.

https://www.bbc.com/news/technology-57009930

[Outcast_Searcher]

$this->bbcode_second_pass_quote('aadbrd', 'S')orry for the thread bump but this was timely.

https://www.bbc.com/news/technology-57009930

[mousepad]

$this->bbcode_second_pass_quote('Outcast_Searcher', '
')Outfits like Nvidia continue to make VERY meaningful progress

[AdamB]

$this->bbcode_second_pass_quote('mousepad', ' ')Yes I'm much richer now, stinking rich compared to 40 years ago. But happier? Not one bit. Are you?

[mousepad]

$this->bbcode_second_pass_quote('AdamB', '')$this->bbcode_second_pass_quote('mousepad', ' ')Yes I'm much richer now, stinking rich compared to 40 years ago. But happier? Not one bit. Are you?

[AdamB]

$this->bbcode_second_pass_quote('mousepad', '')$this->bbcode_second_pass_quote('AdamB', '')$this->bbcode_second_pass_quote('mousepad', ' ')Yes I'm much richer now, stinking rich compared to 40 years ago. But happier? Not one bit. Are you?

[Outcast_Searcher]

$this->bbcode_second_pass_quote('mousepad', '')$this->bbcode_second_pass_quote('Outcast_Searcher', '
')Outfits like Nvidia continue to make VERY meaningful progress

[aadbrd]

$this->bbcode_second_pass_quote('mousepad', '
')They make progress. But is it meaningful?

[jedrider]

$this->bbcode_second_pass_quote('aadbrd', '')$this->bbcode_second_pass_quote('mousepad', '
')They make progress. But is it meaningful?