Re: [RFC][PATCH]: CRC32 is limiting at COPY/CTAS/INSERT ... SELECT + speeding it up
Marc Cousin <cousinmarc@gmail.com>
From: Marc Cousin <cousinmarc@gmail.com>
To: pgsql-hackers@postgresql.org
Date: 2010-11-03T08:03:21Z
Lists: pgsql-hackers
The Saturday 30 October 2010 11:05:17, Andres Freund wrote : > Hi, > > This thread died after me not implementing a new version and some potential > license problems. > > I still think its worthwile (and I used it in production for some time) so > I would like to implement a version fit for the next commitfest. > > The code where I started out from is under the zlib license - which is to > my knowledge compatible with PGs licence. Whats the position of HACKERS > there? There already is some separately licenced code around and were > already linking to zlib licenced code... > > For simplicitly I asked Mark Adler (the original Copyright Owner) if he > would be willing to relicence - he is not. > > For anybody not hording all old mail like me here is a link to the archives > about my old patch: > > http://archives.postgresql.org/message- > id/201005202227.49990.andres@anarazel.de > > > Andres I forgot to report this a few months ago: I had a very intensive COPY load, and this patch helped. The context was a server that was CPU bound on loading data (8 COPY on the same table in parallel, not indexed). This patch gave me a 10% boost in load time. I don't have the figures right now, but I could try to do this test again if this can help. At that time, I just tried it out of curiosity, but the load time was sufficient without it, so I didn't spend more time on it.