High CPU usage after partitioning

Hello,

I'm running postgresl 9.0. After partitioning a big table, CPU usage raised
from average 5-10% to average 70-80%.

- the table contains about 20.000.000 rows
- partitions are selected using a trigger, based on an indexed field, a
date (IF date_taken >= x AND date_taken < y)
- I created 5 partitions, the 2012 one now contains most of the rows. The
2013 partition is the "live" partition, mostly insert, a few select based
on the above indexed field. The 2013, 2014, 2015 partitions are empty
- constraint execution is on.

I have 2 weeks CPU usage reports and the pattern definately changed after I
made the partitions. Any idea?

thanks,

--
rd

This is the way the world ends.
Not with a bang, but a whimper.