Hi, I am running Debian stable with home-built kernels on a number of KVM hosts and a bigger number of KVM VMs. With 4.14, I have an interesting phenomenon on _one_ of my hosts, while all other hosts run fine. All systems are reasonably similar to each other.
On the affected host, VMs freeze at a rate about two or three per day. They just stop dead in their tracks, console and serial console become unresponsive, ping stops, they don't react to virsh shutdown, only to virsh destroy. They do, however, take a noticeable part of CPU resources when they're in this state, up to a full CPU core. What's left in syslog of a VM is unsuspicious, the host logs don't have anything uncommon. When I start a VM that allocates a lot of memory (like the 8 GB Windows VM that I use for bookkeeping and taxes), it happens that two to five of the Linux VMs freeze in the same second. The affected host is a Thinkpad T520 with 16 Gig of RAM and an Intel(R) Core(TM) i5-2520M that is neither under noticeable load nor under memory pressure (it can afford 8 Gig of disk cache). When I boot the host back to 4.13.11, things are just fine and the machine is chugging away painlessly for days. When I boot 4.14, the VM freeze phenomenon usually appears in the first 24 hours. The other VM hosts (ranging from a small PC Engines APU to a bigger 48 Gig Server in Housing) run just fine with 4.14 as well. Any ideas? Greetings Marc -- ----------------------------------------------------------------------------- Marc Haber | "I don't trust Computers. They | Mailadresse im Header Leimen, Germany | lose things." Winona Ryder | Fon: *49 6224 1600402 Nordisch by Nature | How to make an American Quilt | Fax: *49 6224 1600421
