Kubelet and kube-proxy both had loops to ensure that their iptables
rules didn't get deleted, by repeatedly recreating them. But on
systems with lots of iptables rules (ie, thousands of services), this
can be very slow (and thus might end up holding the iptables lock for
several seconds, blocking other operations, etc).
The specific threat that they need to worry about is
firewall-management commands that flush *all* dynamic iptables rules.
So add a new iptables.Monitor() function that handles this by creating
iptables-flush canaries and only triggering a full rule reload after
noticing that someone has deleted those chains.
Work around Linux kernel bug that sometimes causes multiple flows to
get mapped to the same IP:PORT and consequently some suffer packet
drops.
Also made the same update in kubelet.
Also added cross-pointers between the two bodies of code, in comments.
Some day we should eliminate the duplicate code. But today is not
that day.
- Move from the old github.com/golang/glog to k8s.io/klog
- klog as explicit InitFlags() so we add them as necessary
- we update the other repositories that we vendor that made a similar
change from glog to klog
* github.com/kubernetes/repo-infra
* k8s.io/gengo/
* k8s.io/kube-openapi/
* github.com/google/cadvisor
- Entirely remove all references to glog
- Fix some tests by explicit InitFlags in their init() methods
Change-Id: I92db545ff36fcec83afe98f550c9e630098b3135