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Router CPU near 100% usage while bandwidth usage is like 60%. How to decrease CPU and increase BW?


New Member
Mar 30, 2021
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The router is having QoS enabled with 1 rule to ensure that each LAN computer has certain guaranteed bandwidth.
The bandwidth flowing through the router is mainly thanks to single Linux Debian computer on which is starting a Wireguard VPN tunnel (tunnel ends in the internet).
This router was able to reach its declared bandwidth capacity before, under same client computers apps usage. I am unsure what to exactly do to find the cause of the high CPU usage on the router to allow higher throughput. What is your experience with routers CPUs utilization causes?
So far i have tried to disable QoS (bandwidth share control), it seemingly decreased CPU load, but hard to guess.
What is your opinion regarding packets and VPN tunnel (Wireguard) in regards to router CPU? (again, note that router is not doing encryption/decription of the tunnel, its done on the computers)
Thank you in advance
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