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Comment by brucehoult | Hacker News Reader

Nice! Looks like an interesting mid-point between xv6 (modern reimplementation of Sixth Edition Unix from 1975 e.g. Lion book) and a full Linux kernel.

Great to see it runs on the LicheeRV Nano, a $9 RISC-V board with 1.0 GHz 64 bit CPU (C906) with MMU, FPU, 128 bit vector unit (RVV draft 0.7.1) and 256 MB of in-package DDR3. That's comparable to a midlife Pentium III or PowerPC G4.

It should be a very easy port to the Milk-V Duo 256M (same SG2002 SoC) or Duo S (SG2000 with 512 MB RAM for $9.90) or original Duo (closely related CV1800B with 64 MB RAM for $5).

No network or block device support at present, and no multi-core either, by the looks.

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"No network or block device support at present, and no multi-core either, by the looks."

The first versions of Linux I used did not have multi-core support and I can imagine a Linux without networking, but no block devices?

Does that mean just character devices? How does the FAT driver work then?

It supports a read-only boot drive, but other than that just tempfs -- just like running a LiveCD version of Ubuntu etc.

Implementing those things is on the TODO list.

The earliest versions of Linux were pretty much just a terminal emulator for the PC console. Gotta start somewhere!

It looks like TILCK uses RAM images to provide FAT support, which is mainly used for initrd.

A G4 with Altivec was almost on par on a PIV with SSE2 for multimedia.

Multimedia is important for some uses, not for others.

And what speed G4, against what speed Pentium 4?

G4 started from 450 MHz and went to 1.6 GHz, with several different µarch along the way.

Conversely, the Pentium 4 ranged from 1.3 GHz to 3.8 GHz.

G4 and P3 at least covered a nearly identical MHz range, and with similar MHz in the market at the same times.

Pentium 4 had an exceptionally long pipeline to be able to hit higher frequencies, trading-off high IPC numbers in the process, most of the time. On top of that, Pentium 4 also “looped” the same instruction while waiting data resulting in lower efficiency and higher heat output.

So, I assume, they are “step by step” comparable. i.e. slowest P4 equal to slowest G3 and they are again equal at next stepping and so on.

Core Duo's are almost duct-taped PIIIs.

Isn't Core Duo is an evolution of Pentium-M which is an evolution of Pentium 3, omitting Pentium 4 in the process like an unwanted child?

Feels like they rolled back a couple of commits, forked to a new branch and started over...

Which given hardware description languagesm that might indeed have been in the case. :)

It actually was between PIII and IV on capabilities. Altivec allows to play h264 videos on some settings. A Pentium III, well, SSE and FFMPEG can do magic, but not as well as Altivec. SSE2 it's better, much better. Basically the minimum for x86 and 'modern' browsers.

On the architecture itself, PowerPC did far more per cycle.

The a version of the Pentium 4 was slower than the Pentium IIi per clock (launch model) and used goofy rambus memory

Their prediction about rambus hasn't aged well, but the technical advantages vs. SDRAM of the time are still interesting:

https://www.hardwarecentral.com/sdram-vs-rdram-facts-and-fan...

Surprisingly enough the N64 used RDRAM (and supported a memory upgrade, lowering the cost of the console at launch but enabling an upgrade path for games that needed more memory.)

I recall folks claiming the G5 outperformed Pentium D, but I had both and not only was the Pentium snappier, "Roxio Toast" could burn a DVD in half the amount of time on it.

Maybe it was a software optimization issue and Toast just didn't use Altivec, but I was not surprised at all when Apple moved to Intel.

it was mostly marketing "oooh altivec can do sooo many FP calculations that it has to be licensed as a deadly weapon". Same kinda marketing for MMX "if a programmer was an a MMX guru then basically you have a supercomputer bro"

That's all great but it was all awaiting a killer app to make it all worth it and reasonable, versus random programs rarely supporting it for a little boost.

And the name of that killer app, using these DSP type features? Local AI.

In case of Altivec, having it or not was THE difference betweeen watching a video in MPlayer or a slideshow.

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