On 12/28/23 12:41, Sean Flaherty wrote:
I'm rather new to the mailing list, are there any additional steps I should take (i.e. posting to pgsql-hackers, etc.)?
For what purpose? You are seeing differences in compression strategies between lz4 and pglz. The 'fix' would be to go back to pglz.
On Thu, Dec 28, 2023 at 11:23 AM Adrian Klaver <adrian.klaver@xxxxxxxxxxx <mailto:adrian.klaver@xxxxxxxxxxx>> wrote:On 12/28/23 09:13, Sean Flaherty wrote: > Follow-up: > Working with AWS, we found that starting in RDS Postgres 15, the > default_toast_compression parameter is set to use lz4 compression > instead of pglz. This resulted in the increased json storage size we > were seeing. > > I have been able to reproduce the increased storage size on RDS Postgres > and using my local docker instance of postgres 15.5 by changing the > local default_toast_compression value in postgresql.conf. > > I have attached the test script we use to create a table, insert some > test records and a query to test the JSON data size on disk. I can confirm I see the same results using Postgres 16 installed from the PGDG repo on Ubuntu 22.04. That the lz4 data size is greater then the pglz data size. > > > Kind regards, > Sean >-- Adrian Klaveradrian.klaver@xxxxxxxxxxx <mailto:adrian.klaver@xxxxxxxxxxx>
-- Adrian Klaver adrian.klaver@xxxxxxxxxxx
