Hi,
I am getting a frozen guest when migrating from an Opteron 6274 host
(amd
fam15h) to
an Opteron 6174 host (amd fam10h). The live migration completes
succesfully, but
the guest is frozen: vcn screen is still there, but no input is
possible and
no kernel output is seen. Trying "c" on the qemu-monitor does not
help.
I am using "-cpu Opteron_G3" which I assumed would be ok for both
host cpus.
In the opposite direction (migrating from an amd fam10h host to an
amdfam15h
host) the guest continues to run on the destination. However, on most
of these
successfull live migrations, I notice a "clocksource unstable"
message on the
guest kernel (using the default kvm-clock clocksource) e.g.
Clocksource tsc unstable (delta = -1500533439 ns)
Same situation (guest runs on destination with clocksource unstable
message)
happens when migrating between fam15h hosts (I have not tried between
fam10h
hosts)
Changing the clocksource (tsc, acpi_pm, hpet) does not solve the
issue.
Also tried with "-cpu kvm64" with same result.
qemu-kvm version: 0.15.1, 1.0 or qemu-kvm/master
Host kernel: 3.0.15 (on both hosts)
Guest kernel: 3.0.6 or 3.2
this is the qemu-kvm command line used on the source host:
"
kvm -enable-kvm -m 1024 -smp 1 -cpu Opteron_G3,check -drive \
file=/opt/test.img,if=none,id=drive-virtio-disk1,format=raw,cache=writethrough,boot=on
-device
virtio-blk-pci,bus=pci.0,addr=0x5,drive=drive-virtio-disk1,id=virtio-disk1
-monitor stdio -vnc 0.0.0.0:6 -vga std -chardev pty,id=charserial0
-device
isa-serial,chardev=charserial0,id=serial0 -usb -device
usb-tablet,id=input0
"
The destination host has the same command line with an added
"-incoming
tcp:4444". I have mainly tested this with non-shared storage (but
also shared
storage has the same result). Migration is triggered with "migrate -b
tcp:destip:4444"
Do the TSC microarchitecture changes in amdfam15h (see AMD SW
optimiization
guide for fam15h, 47414 Rev 3.02 Appendix E) affect pvclock stability
on
migration in same family or across families?
cpuid information follows in case it's helpful.
..snip..
Hi, I can confirm this problem still exists in live migrations between
Opteron 6128HE and Opteron 6274.
Live migration from 6100-series to 6200-series work, but never from
6200 to 6100.
Issue is reproducible and symptoms are identical with previous poster.
I have tested with 3.10.5 host-kernel and 1.7 qemu, also with 3.1.4 and
>1.0 qemu, guest kernel seems to be irrelevant at this point (as it
crashes any OS).
I would say this needs attention, and I'm willing to help to get this
sorted out.
Thanks for your thoughts.
Yours
Markus Kovero
+358 40 577 1129