Re: [RFC][PATCH]: CRC32 is limiting at COPY/CTAS/INSERT ... SELECT + speeding it up

On Friday 21 May 2010 05:40:03 Robert Haas wrote:
> On Thu, May 20, 2010 at 4:27 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:
> > I looked a bit around for faster implementations of CRC32 and found one
> > in zlib. After adapting it (pg uses slightly different computation (non-
> > inverted)) I found that it increases the speed of the CRC32 calculation
> > itself 3 fold.
>
> But zlib is not under the PostgreSQL license.
Yes. But:
1. the zlib license shouldn't be a problem in itself - pg_dump also already
links to zlib
2. I planned to ask Mark Adler whether he would support relicising those bits.
I have read some other discussions where he was supportive of doing such a
thing
3. Given that idea was posted publically on the usenet it is not hard to
produce an independent implementation.

So I do not see any big problems there... Or am I missing something?

Greetings,

Andres

/* zlib.h -- interface of the 'zlib' general purpose compression library
version 1.2.2, October 3rd, 2004

Copyright (C) 1995-2004 Jean-loup Gailly and Mark Adler

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Jean-loup Gailly jloup(at)gzip(dot)org
Mark Adler madler(at)alumni(dot)caltech(dot)edu

*/