Troubleshooting Tip: High CPU utilization due to the initXXXXXXXXXXX process

1. Check the process using more CPU:

FGT_A $ diagnose sys top-all 3 30 10
Run Time: 75 days, 7 hours and 57 minutes
6U, 0N, 2S, 87I, 5WA, 0HI, 0SI, 0ST; 24101T, 15590F
 initXXXXXXXXXXX 1 R 97.0 0.0
        bcm.user 228 S < 12.0 0.4
           snmpd 2454 S 6.5 0.4

2. Check the crash log via 'diag debug crashlog read' or enable the following debugs. 

diagnose debug disable
diagnose debug reset
diagnose debug console timestamp enable
diagnose debug enable
diagnose test application init 2
diagnose test application init 3
diagnose debug application init -1

To disable debugs:

diagnose debug disable

It may be seen as a loop of stack outputs:

16376: 2023-08-31 07:39:45 dbg_stack_print_to_b 123 0.000000 1
16377: 2023-08-31 07:39:45 dum_signal 1549 0.000000 1
16378: 2023-08-31 07:39:45 dbg_stack_print_to_b 123 0.000077 1
16379: 2023-08-31 07:39:45 dum_signal 1549 0.000077 1
16380: 2023-08-31 07:39:45 dbg_stack_print_to_b 123 0.000153 1 

3. INIT is the parent of all userspace processes, it cannot be killed.

Workaround:

To kill the init process, restart the FortiGate.

Final solution: 

Upgrade to v7.4.4.