Performance down with JDBC 42

[Abraham, Danny]

Hi,

Asking for help with a JDBC related issue.
Environment: Linux 7.9 PG 14.9 , very busy PG Server.

A big query - 3 unions and about 10 joins runs :
- 70ms on psql , DBeaver with JDBC 42  and  in our Server using old JDBC 9.2
- 2500 ms in our Server using new JDBC 42 driver. ( and  this is running many 
times) 

Question: Is there a structured way to identify optimization setup ( Planner 
Method s ) changes?
Are there any known changes specific to JDBC 42. 
Capture a vector of session optimization setup?  
Any other Idea ?

Thanks

Danny

Re: Performance down with JDBC 42

[Laurenz Albe]

On Sat, 2023-11-04 at 19:08 +, Abraham, Danny wrote:
> Asking for help with a JDBC related issue.
> Environment: Linux 7.9 PG 14.9 , very busy PG Server.
> 
> A big query - 3 unions and about 10 joins runs :
> - 70ms on psql , DBeaver with JDBC 42  and  in our Server using old JDBC 9.2
> - 2500 ms in our Server using new JDBC 42 driver. ( and  this is running many 
> times) 
> 
> Question: Is there a structured way to identify optimization setup ( Planner 
> Method s ) changes?
> Are there any known changes specific to JDBC 42. 

What I would do is enable auto_explain and look at the execution plan
when the statement is run by the JDBC driver.  Then you can compare the
execution plans and spot the difference.

Yours,
Laurenz Albe