Re: jsonb format is pessimal for toast compression

On 08/08/2014 06:17 AM, Tom Lane wrote:
> I looked into the issue reported in bug #11109.  The problem appears to be
> that jsonb's on-disk format is designed in such a way that the leading
> portion of any JSON array or object will be fairly incompressible, because
> it consists mostly of a strictly-increasing series of integer offsets.
How hard and how expensive would it be to teach pg_lzcompress to
apply a delta filter on suitable data ?

So that instead of integers their deltas will be fed to the "real"
compressor


-- 
Hannu Krosing
PostgreSQL Consultant
Performance, Scalability and High Availability
2ndQuadrant Nordic OÜ