Re: Patent issues and 8.1

Ühel kenal päeval (kolmapäev, 26. jaanuar 2005, 15:38+1100), kirjutas
Neil Conway:
> Bruce Momjian wrote:
> > So if we have to address it we call it 8.0.7 or something. My point is
> > that we don't need to address it until we actually find out the patent
> > is being enforced against someone, and that possibility is quite unlikely.
>
> IMHO, the patent issue is *not* a "potential problem" for a lot of
> people, it *is* a problem -- it makes people uncomfortable to be
> deploying software that they know might cause them legal headaches down
> the line.

If people see we are scared by so little, I fear that someone will pop
up another "potential patent problem" just after we have reverted to
LRU. Or even better - a day or two before releasing 8.0.x withr RLU fix.

> It also makes life difficult for people distributing
> commercial versions of PostgreSQL.

Simple repackaging should not be a basis of "commercial" version. If
they want it, they could

a) distribute OSS version and sell support

b) test your LRU backpatch and sell (a likely worse performing) version
with that.

c) implement a better-than-ARC cache replacement scheme, and sell that.
If they are really pissed off at PGDG they could even apply for a patent
to that scheme and gain "competitive advantage" in their investors eyes.

> I've posted a patch to -patches that replaces ARC with LRU. The patch is
> stable -- I'll post some code cleanup for it tomorrow, but I've yet to
> find any bugs despite a fair bit of testing.

Have you done any performance comparisons with your LRU patch our 8.0
PgARC implementation.

IIRC the differences between 7.4 and 8.0 were best visible on really
heavy workloads, like the ones tested at OSDL.

If the performance does not matter, the simplest solution would be
setting postgres internal cache to 0 bytes and rely just on OS buffers.
That stops infringement immediately as one is not *using* any patented
technologies then.

> I think the best solution is to replace ARC with LRU in 8.0.1 or 8.0.2,
> and develop a better replacement policy during the 8.1 development cycle.

That could be the best solution for those worried about it (commercial
distributors mainly) but for the others a better tested and stable ARC-
like solution we have implemented and tested now is probably still
better.

AN UNRELATED SUGGESTION:

Could anybody take the patent application and comment it claim-by-claim
marking up things having prior art (like claim 1 - keeping two lists),
so that when we start designing our ARC replacement, we know what points
we can safely "infringe" (IIRC some points involved doing LRU-like
stuff, so if we decide to be unconditionally terrified by the patent
application we should avoid LRU as well).

Then we could put up the commented version on our website or perhaps
havet it up at http://www.groklaw.net/ for comments from larger
community already familiar with IP issues ;).

Slashdot would be another place to ask for comments/prior art.

My point is, that while the IBM's patent as a whole could be worth
patent protection, each and every claim in it separately is probably
not.

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