We have installed RHQ monitoring system http://rhq-project.org/display/RHQ/Home. From that time our program started to slow down. It happens every day at 9:20~30 AM. Can RHQ slow down system? Because our admin claims that the RHQ can not slow down the system :)
System consist of:
If it happens every day at the same time, monitor what the machine is doing at this time. The output of "top", "vmstat" and "iotop" would probably be a good start.