Re: Optimizing pglz compressor

On 2013-03-06 09:36:19 -0600, Merlin Moncure wrote:
> On Wed, Mar 6, 2013 at 8:32 AM, Joachim Wieland <joe(at)mcknight(dot)de> wrote:
> > On Tue, Mar 5, 2013 at 8:32 AM, Heikki Linnakangas
> > <hlinnakangas(at)vmware(dot)com> wrote:
> >> With these tweaks, I was able to make pglz-based delta encoding perform
> >> roughly as well as Amit's patch.
> >
> > Out of curiosity, do we know how pglz compares with other algorithms, e.g. lz4 ?
>
> This has been a subject of much recent discussion. It compares very
> poorly, but installing a new compressor tends to be problematic due to
> patent concerns (something which I disagree with but it's there). All
> that said, Heikki's proposed changes seem to be low risk and quite
> fast.

Imo the licensing part is by far the smaller one. The interesting part
is making a compatible change to the way toast compression works that
supports multiple compression schemes. Afaics nobody has done that work.
After that the choice of to-be-integrated compression schemes needs to
be discussed, sure.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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