"snmp ifmib ifindex persist" or not?

[Lutz]

Hello,

I installed a new 10G interface in a catalyst 3560E and refeshed in Cacti the interfaces of this device.
After that I saw some (existing) graphs changing his view, some showed no input traffic, but there is still traffic.
Not all graphs of this device are affected.

switch#sh run | i persist
snmp ifmib ifindex persist

IOS Version 12.2(50)SE3
Cacti Version 0.8.7b

I think the ifindex is changing, but why?

Regards
Lutz