RE: Having query cache in core

From: Robert Haas [mailto:robertmhaas@gmail.com]
> That's not my experience.  I agree that plan caching isn't important
> for long-running queries, but I think it *is* potentially important
> for fast queries with fast planning time.  Even when the planning time
> is fast, it can be a significant percentage of the execution time.
> Not long ago, we had a case at EDB where a customer was getting custom
> plans instead of generic plans and that resulted in a significant
> reduction in TPS.

I have the same experience with our customers.  Their batch applications suffered from performance compared to Oracle
andSQL Server.  Those apps repeatedly issued simple SELECT statements that retrieve a single row.
 

Regards
Takayuki Tsunakawa