I believe I've found the issue. When NM sees an interface, it brings it up. It then requests state. If this state is "UNKNOWN" (as opposed to "DOWN" or "UP") it brings the interface up again and requests state again.
This results in an infinite and unrestrained loop. NetworkManager needs to back-off in this scenario and only poll every so often (like maybe once per second). Note, this scenario is occurring on an interface that is a fixed 10G (no auto-negotiation). The unknown state is shown when it if is up, but there is no physical link (because the MAC doesn't do AN, it's reports link active, always). I'm not sure if this state in the ethernet driver is buggy or not. I'm still investigating that. However, NM putting itself into a tight CPU intensive loop is fixable and the right thing to do, either way. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1111926 Title: NetworkManager increases CPU utilization To manage notifications about this bug go to: https://bugs.launchpad.net/network-manager/+bug/1111926/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
