100
you are viewing a single comment's thread
view the rest of the comments
[-] vrighter@discuss.tchncs.de 5 points 1 year ago

slight correction. vector processing is available on almost no common architectures. What most architectures have is SIMD instructions. Which means that code that was written for sse2 cannot and will not ever make use of the wider AVX-512 registers.

The risc-v isa is going towards the vector processing route. The same code works on machines with wide vector registers, or ones with no real parallel ability, but will simply loop in hardware.

Simd code running on a newer cpu with better simd capabilities will not run any faster. Unmodified vector code on a better vector processor, will run faster

[-] mindbleach@lemmy.world 3 points 1 year ago

Fancier tech co-opting an existing term doesn't make the original use wrong.

Any parallel array operation in hardware is vector processing.

[-] vrighter@discuss.tchncs.de 1 points 1 year ago

fancy, vector processing predated simd. It's how cray supercomputers worked in the 90s. You're the one co opting an existing term :)

And it is in fact a big deal, with several advantages and disadvantages to both.

[-] mindbleach@lemmy.world 1 points 1 year ago
[-] vrighter@discuss.tchncs.de 1 points 1 year ago

from the very first paragraph in the page:

a vector processor or array processor is a central processing unit (CPU) that implements an instruction set where its instructions are designed to operate efficiently and effectively on large one-dimensional arrays of data called vectors. This is in contrast to scalar processors, whose instructions operate on single data items only, and in contrast to some of those same scalar processors having additional single instruction, multiple data (SIMD) or SWAR Arithmetic Units.

Where it pretty much states that scalar processors with simd instructions are not vector processors. Vector processors work on large 1 dimensional arrays. Call me crazy, but I wouldn't call a register with 16 32-bit values a "large" vector.

It also states they started in the 70s. That checks out. Which dates were you referring to?

[-] mindbleach@lemmy.world 1 points 1 year ago

This is rapidly going to stop being a polite interaction if you can't remember your own claims.

SIMD predates the term vector processing, and was in print by 1966.

Vector processing is at least as old as the Cray-1, in 1975. It was already automatically parallelizing what would've been loops on prior hardware.

Hair-splitting about whether a processor can use vector processing or exclusively uses vector processing is a distinction that did not exist at the time and does not matter today. What the overwhelming majority of uses refer to is basically just SIMD extensions. Good luck separating the two when SIMT is a thing.

[-] vrighter@discuss.tchncs.de 1 points 1 year ago

I'm not hair splitting over whether they can or not. scalar processors with simd cannot do vector processing, because vector processing is not simd.

yes an array of values can be called a vector in a lot of contexts. I could also say that vector processing involves dynamically allocated arrays, since that's what c++ calls them. A word can be used in mulmiple contexts. When the word vector is used in the term "vector processor" it specifically excludes scalar processors with simd instructions. It refers to a particular architecture of machine. Just being able to handle a sequence of numbers is not enough. Simd can do it, as can scalar processors (one at a time, but they still handle "an array of numbers"). You can't even say that they necessarily have to execute more than one at a time. A superscalar processor without simd can do that as well.

A vector processor is a processor specifically designed to handle large lists. And yes, I do consider gpus to be vector processors (exact same shader running on better vector hardware, does run faster.) They are specifically designed for it. simd on a scalar processor is just... not

[-] mindbleach@lemmy.world 1 points 1 year ago

A word can be used in mulmiple contexts.

Says user insisting an umbrella term has one narrow meaning.

A meaning that would include the SoundBlaster 32.

this post was submitted on 05 Aug 2023
100 points (97.2% liked)

No Stupid Questions

35868 readers
972 users here now

No such thing. Ask away!

!nostupidquestions is a community dedicated to being helpful and answering each others' questions on various topics.

The rules for posting and commenting, besides the rules defined here for lemmy.world, are as follows:

Rules (interactive)


Rule 1- All posts must be legitimate questions. All post titles must include a question.

All posts must be legitimate questions, and all post titles must include a question. Questions that are joke or trolling questions, memes, song lyrics as title, etc. are not allowed here. See Rule 6 for all exceptions.



Rule 2- Your question subject cannot be illegal or NSFW material.

Your question subject cannot be illegal or NSFW material. You will be warned first, banned second.



Rule 3- Do not seek mental, medical and professional help here.

Do not seek mental, medical and professional help here. Breaking this rule will not get you or your post removed, but it will put you at risk, and possibly in danger.



Rule 4- No self promotion or upvote-farming of any kind.

That's it.



Rule 5- No baiting or sealioning or promoting an agenda.

Questions which, instead of being of an innocuous nature, are specifically intended (based on reports and in the opinion of our crack moderation team) to bait users into ideological wars on charged political topics will be removed and the authors warned - or banned - depending on severity.



Rule 6- Regarding META posts and joke questions.

Provided it is about the community itself, you may post non-question posts using the [META] tag on your post title.

On fridays, you are allowed to post meme and troll questions, on the condition that it's in text format only, and conforms with our other rules. These posts MUST include the [NSQ Friday] tag in their title.

If you post a serious question on friday and are looking only for legitimate answers, then please include the [Serious] tag on your post. Irrelevant replies will then be removed by moderators.



Rule 7- You can't intentionally annoy, mock, or harass other members.

If you intentionally annoy, mock, harass, or discriminate against any individual member, you will be removed.

Likewise, if you are a member, sympathiser or a resemblant of a movement that is known to largely hate, mock, discriminate against, and/or want to take lives of a group of people, and you were provably vocal about your hate, then you will be banned on sight.



Rule 8- All comments should try to stay relevant to their parent content.



Rule 9- Reposts from other platforms are not allowed.

Let everyone have their own content.



Rule 10- Majority of bots aren't allowed to participate here.



Credits

Our breathtaking icon was bestowed upon us by @Cevilia!

The greatest banner of all time: by @TheOneWithTheHair!

founded 1 year ago
MODERATORS