Re: processor affinity

Nick Piggin
2004-09-30T02:41:30Z

Jeff V. Merkey wrote:
> Alan Cox wrote:
>
>> On Maw, 2004-09-28 at 17:02, Jeff V. Merkey wrote:
>>
>>
>>>>> http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=/netahtml/search-bool.html&r=2&f=G&l=50&co1=AND&d=ptxt&s1=merkey.INZZ.&OS=IN/merkey&RS=IN/merkey
>>>>>
>>>>>
>>>>
>>>> Wow, I never knew about that.
>>>>
>>>> But guess who wrote the affinity system calls? :)
>>>>
>>
>>
>>
>>
>>> I wrote them first, and coined the term.
>>
>>
>> Cute but GCOS3 had affinity syscalls for batch processing in the 1970's
>> and I don't believe it was original even then.
>>
>>
>
> Using them for Intel Cache affinity was new at the time. Intel SMP
> hardware was not readily available at the time and was in
> its infancy in 1993 when this was developed.

That is amazingly specific - I suppose using it for cache affinity on
earlier processors wouldn't count :)

Joking aside, this doesn't seem like it would apply to Linux's scheduler.
We don't use a global queue, and we don't implement hard affinities with
local queues, but with a specific bitmask of cpus.

Of course, I don't really have any idea how to interpret patents...