On 08/14/2014 07:24 PM, Tom Lane wrote:
> We can certainly reduce that. The question was whether it would be
> worth the effort to try. At this point, with three different test
> data sets having shown clear space savings, I think it is worth
> the effort. I'll poke into it tomorrow or over the weekend, unless
> somebody beats me to it.
Note that I specifically created that data set to be a worst case: many
top-level keys, no nesting, and small values. However, I don't think
it's an unrealistic worst case.
Interestingly, even on the unpatched, 1GB table case, the *index* on the
JSONB is only 60MB. Which shows just how terrific the improvement in
GIN index size/performance is.
--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com