How to measure CPU time spent by kernel on ipsec and NAT?

Question

linux

There is a server with a firewall and NAT on it, libreswan and one VPN are also raised. I want to see the CPU load when transferring a file over VPN. top showed emptiness - sy 0.2% id 99.8% - I don't believe (c). Is there an option to get information from the kernel, how much time it spends converting packets? It is possible in real time.

Answer 1

top showed emptiness - sy 0.2% id 99.8% - don't believe

So it is.
Open 3 windows in one top in another htop in the third ps aux click.

Answer 2

Utilities for diagnosing problems with performance ...
But in general, in order to understand what or who loads the system in time, you need to collect data, accumulate them, then build graphs, that is, in fact, you need a simple monitoring system, for example, the same munin is simple in installation and configuration, and there are a lot of manuals on it.

Answer 3

1) Make sure that your data is really going through ipsec + vpn
2) Load the router with iperf utilities
3) Use top/htop to view real-time statistics. If something is considered, then it must be shown in the processes and kernel loading