views much slower in 9.3 than 8.4

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



We have views that run from 20x to failing to complete at all in 9.4.1 whereas they finished in seconds in 8.4.7 on the same platform.

After upgrading from 8.4 to 9.4, I ran ANALYZE on the entire DB.  Performance improved for some but not all of the views.

Here is the explain-analyze output from one of the slow views in 9.4: 
http://explain.depesz.com/s/36n

Unfortunately I have no way of producing an 8.4 plan.

While acknowledging that nested loops and sequential table scans account for 85% of the execution time which suggests that a better query may be needed, why would the same query run in seconds on 8.x but take minutes on 9.x?   

Did the planner change significantly between the two releases?   Is there any way to compel the 9.4 planner to produce an 8.4 plan?  

Thanks in advance for you assistance.




-- 
Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance





[Postgresql General]     [Postgresql PHP]     [PHP Users]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Yosemite]

  Powered by Linux