Technical Tip: Transient high system CPU condition with src-vis CPU load

[tgirard]

Description	This article describes what to do when a device experiences transient high system CPU (softirq) and a recurring level of src-vis CPU usage in user space.
Scope	All supported versions of FortiGate.
Solution	src-vis daemon/process is used for device identification configured on the interfaces, and it is used to gather information about the devices operating on the network: MAC address. IP address. Operating system. Hostname. User name. How long ago the device was detected and on which FortiGate interface. The device experiences transient high system CPU (softirq) and a recurring level of src-vis CPU usage in user space. A CPU profiling taken at a time of high system CPU would show a pattern like: 0xffffffffa008fc95: 31 capwap_npu_del_vap+0x3565/0x3c60 0xffffffff80543b00: 6 __copy_skb_header+0x1e0/0x4c0 0xffffffff80550124: 6 dev_hard_start_xmit+0x84/0x270 The device-identification is enabled on many interfaces, and disable device identification on all interfaces to clear the issue.