Why not go with Linux 3.19 ? You can just install it by running:
sudo apt-get install linux-generic-lts-vivid It is by far, much more stable than Linux 3.13 (specially the network stack)... ;-) On 6 October 2015 at 11:36, Jim <ubuntu...@go-draytek.ca> wrote: > This is NOT fixed by 3.13.0-33.58. It continues to persist even with > 3.13.0-65.106 (and 3.13.0-63.103). > > I have around 10 VMs running but ONE in particular disconnects from the > network every hour or so. > > I had this issue previously but it was initially gone on Ubuntu 14.04 > LTS but had come back recently - perhaps some kernel regression ? > > dmesg shows > > [42524.196629] kvm: zapping shadow pages for mmio generation wraparound > [42538.140013] br0: port 2(vnet0) entered learning state > [42538.268017] br1: port 2(vnet1) entered learning state > [42553.180008] br0: topology change detected, propagating > [42553.180015] br0: port 2(vnet0) entered forwarding state > [42553.308008] br1: topology change detected, propagating > [42553.308014] br1: port 2(vnet1) entered forwarding state > > (and NIC connection is gone) > > It's not clear if this is just co-incidence or if this is a pointer to > the issue. > > This VM is unusual in my VMs becuase it is the only one with 2 NIC > connections to br1 and br0. All the others connect to just br0. Those > others work OK. > > Happy to try suggestions to track this down. > > -- > You received this bug notification because you are subscribed to a > duplicate bug report (1341195). > https://bugs.launchpad.net/bugs/1346917 > > Title: > Using KSM on NUMA capable machines can cause KVM guest performance and > stability issues > > To manage notifications about this bug go to: > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1346917/+subscriptions -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1346917 Title: Using KSM on NUMA capable machines can cause KVM guest performance and stability issues Status in linux package in Ubuntu: Fix Released Status in linux source package in Trusty: Fix Released Bug description: [Impact] When using KVM on NUMA machines, both Linux and Windows guests can exhibit very poor performance and potential crashes. Disabling KSM is a known workaround to fix this issue. [Fix] The following patch fixes the issue in our testing: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=64a9a34e22896dad430e21a28ad8cb00a756fefc This patch is present in v3.14-rc1 and onwards. [Test Case] General test case: 1) On a NUMA capable machine, setup the machine as a KVM hypervisor - lscpu should show more than 1 NUMA node 2) Install 4 KVM VMs 3) Run the following in another terminal to ensure that pages_shared and pages_sharing is increasing - watch 'tail /sys/kernel/mm/ksm/*' 4) In another terminal run a program that continually pings each node and alerts on high latencies What we've observed is that in Linux guests, the ping latencies can go into the ~2 second range for a few pings, then return back to the < 1ms range. (This is machine dependent.) In addition, occasionally when running this test with Windows guests we observe BSODs during this test. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1346917/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
