Re: /proc/cpuinfo format - arch dependent!

[Bill Davidsen <davidsen@tmr.com>]

Lennart Sorensen wrote:
> On Mon, May 09, 2005 at 02:00:55PM -0400, Bill Davidsen wrote:
> 
>>Linus did what was probably right then. I would agree that there is room 
>>for something better now. Just to prove it could be done (not that this 
>>is the only or best way):
> 
> 
> I suspect many architecture's /proc/cpuinfo were not decided by Linus at
> all, but by whoever ported linux to that architecture.
> 
> 
>>  cpu0 {
>>    socket: 0
>>    chip-cache: 0
>>    num-core: 2
>>    per-core-cache: 512k
>>    num-siblings: 2
>>    sibling-cache: 0
>>    family: i86
>>    features: sse2 sse3 xxs bvd
>>    # stepping and revision info
>>  }
>>  cpu1 {
>>    socket: 1
>>    chip-cache: 0
>>    num-core: 1
>>    pre-core-cache: 512k
>>    num-siblings: 2
>>    sibling-cache: 64k
>>    family: i86
>>    features: sse2 sse3 xxs bvd kook2
>>    # stepping and revision info
>>  }
> 
> 
> Where does numa nodes fit into that?
> 
> 
>>This is just proof of concept, you can have per-chip, per-core, and 
>>per-sibling cache for instance, but I can't believe that anyone would 
>>make a chip where the cache per core or per sibling differed, or the 
>>instruction set, etc. Depending on where you buy your BS, Intel and AMD 
>>will (or won't) make single and dual core chips to fit the same socket.
> 
> 
> Have you seen the Cell processor?  Multi core with different instruction
> set for the smaller execution cores than the main one.

I'm aware of it, but until someone actually produces a multicore which 
executes the same instruction set (386+P4?) I assume that all the cores 
used by the program will be the same.

I wrote for the DEC Rainbow (8086 and Z80, one did disk and video, one 
did serial+net), and IIRC the memory addresses were shared but the IO 
addresses weren't. Also something I can't easily name which had a 68010 
and 4 bit RISC in a single carrier. Early microcomputer days were fun, 
or at least I thought it was fun to cope with bizarre and unreliable 
hardware when I was young.