Re: ARC patent

Ühel kenal päeval (esmaspäev, 17. jaanuar 2005, 14:48-0500), kirjutas
Tom Lane:
> Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> > Andrew Sullivan wrote:
> >> What will you do if the patent is granted, 8.0 is out there with the
> >> offending code, and you get a cease-and-desist letter from IBM
> >> demanding the removal of all offending code from the Net?
>
> > We can modify the code slightly to hopefully avoid the patent. With the
> > US granting patents on even obvious ideas, I would think that most large
> > software projects, including commercial ones, already have tons of
> > patent violations in their code. Does anyone think otherwise?
>
> I think there is zero probability of being sued by IBM in the near
> future. They would instantly destroy the credibility and good
> relationships they've worked so hard to build up with the entire
> open source community.

Agreed

> However, I don't want to be beholden to IBM indefinitely --- in five
> years their corporate strategy might change. I think that a reasonable
> response to this is to plan to get rid of ARC, or at least modify the
> code enough to avoid the patent, in time for 8.1. (It's entirely likely
> that that will happen before the patent issues, anyway.)

I'd rather like a solution where the cache replacement policy has clean-
enough interface to have many competing algorithms/implementations,
probably even selactable at startup (or even runtime ;).

Firstly, I'm sure that there is no single best strategy (even ARC) for
all kinds of workloads - think OLTP v.s.OLAP.

Secondly, some people might want to use ARC even if and when IBM gets
the patent, even badly enough to license it from IBM. (We are not
obliged to design an interfaces that prevents usage of patented stuff as
this is generally impossible.)

Thirdly, having it as a well-defined component/API might encourage more
research on different algorithms - see how many schedulers linux 2.6
has, both for processes and disk io.

--
Hannu Krosing <hannu(at)tm(dot)ee>