High load since update to RT 4.2.11


I’ve updated our environment to RT 4.2.11 last week.
Since this date I can see that the load of the server (CPU, memory and hdd usage) is growing day by day, and with this RT is getting slower day by day.
I already restarted the server - no success.

DB is running on the same machine, with PostgreSQL 9.3.5

Any idea what I can do?

Best regards