If your IOS device has several CPUs, you must use CISCO-PROCESS-MIB and its object cpmCPUTotal5minRev from the table called cpmCPUTotalTable,
indexed with cpmCPUTotalIndex.
This table allows CISCO-PROCESS-MIB to keep CPU statistics for different physical entities in the router,
like different CPU chips, group of CPUs, or CPUs in different modules/cards.
In case of a single CPU, cpmCPUTotalTable has only one entry.