On 8/26/24 14:49, nikhil raj wrote:
> Hi All,
>
> I've encountered a noticeable difference in execution time and query
> execution plan row counts between PostgreSQL 13 and PostgreSQL 16 when
> running a query on |information_schema| tables. Surprisingly, PostgreSQL
> 16 is performing slower than PostgreSQL 13.
Did you run ANALYZE on the Postgres 16 instance?
> *4PostgreSQL 13.14 (PostgreSQL 13.14 on x86_64-pc-linux-gnu, compiled by
> gcc 11.4.0, 64-bit)*
> Execution plan: PG13.14 Execution Plan
> <https://explain.dalibo.com/plan/ag1a62a9d47dg29d>
>
> *PostgreSQL 16.4 (PostgreSQL 16.4 on x86_64-pc-linux-gnu, compiled by
> gcc 11.4.0, 64-bit)*
> Execution plan: PG16.4 Execution Plan
> <https://explain.dalibo.com/plan/4c66fdfbf2hf9ed2>
Use:
https://explain.depesz.com/
It is easier to follow it's output.
>
>
> Has anyone else experienced similar behavior or could provide insights
> into why PostgreSQL 16 might be slower for this query? Any advice or
> suggestions for optimization would be greatly appreciated.
Yes when ANALYZE was not run on a new instance.
>
> Thank you!
>
> NOTE:- PFA the raw file of explain and analyze below.
>
>
>
>
--
Adrian Klaver
adrian.klaver@aklaver.com