this post was submitted on 24 Oct 2023
212 points (97.7% liked)

Technology

34388 readers
291 users here now

This is the official technology community of Lemmy.ml for all news related to creation and use of technology, and to facilitate civil, meaningful discussion around it.


Ask in DM before posting product reviews or ads. All such posts otherwise are subject to removal.


Rules:

1: All Lemmy rules apply

2: Do not post low effort posts

3: NEVER post naziped*gore stuff

4: Always post article URLs or their archived version URLs as sources, NOT screenshots. Help the blind users.

5: personal rants of Big Tech CEOs like Elon Musk are unwelcome (does not include posts about their companies affecting wide range of people)

6: no advertisement posts unless verified as legitimate and non-exploitative/non-consumerist

7: crypto related posts, unless essential, are disallowed

founded 5 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 2 points 10 months ago* (last edited 10 months ago)

At a minimum they've got to design a wider issue. Current high-performance superscalar chips like the XuanTie 910 (what this laptop's SoC are built around) are only triple-issue (3-wide superscalar), which gives a theoretical maximum of 3 ipc per core. (And even by RISC standards, RISC-V has pretty "small" instructions, so 3 ipc isn't much compared to 3 ipc even on ARM. E.g., RISC-V does not have any comparison instructions, so comparisons need to be composed of at least a few more elementary instructions). As you widen the issue, that complicates the pipelining (and detecting pipeline hazards).

There's also some speculation that people are going to have to move to macro-op fusion, instead of implementing the ISA directly. I don't think anyone's actually done that in production yet (the macro-op fusion paper everyone links to was just one research project at a university and I haven't seen it done for real yet). If that happens, that's going to complicate the core design quite a lot.

None of these things are insurmountable. They just take people and time.

I suspect manufacturing is probably a big obstacle, too, but I know quite a bit less about that side of things. I mean a lot of companies are already fabbing RISC-V using modern transistor technologies.