Re: [Qemu-devel] kvmclock_current_nsec: Assertion `time.tsc_timestamp <= migration_tsc'

[Peter Lieven]

Am 10.02.2015 um 11:17 schrieb Paolo Bonzini:
> On 10/02/2015 11:03, Peter Lieven wrote:
> > My hope was that anyone has observed this post 2.2.0 already and there
> > is a fix available ;-)
> >
> > Can you indicate what info would be helpful debugging this?
> >
> > Cmdline is:
> > /usr/bin/qemu-2.2.0  -enable-kvm  -M pc-i440fx-2.1  -nodefaults -netdev
> > type=tap,id=guest19,script=no,downscript=no,ifname=tap19,vnet_hdr
> > -device virtio-net-pci,netdev=guest19,mac=52:54:00:80:00:55 -netdev
> > type=tap,id=guest20,script=no,downscript=no,ifname=tap20,vnet_hdr
> > -device virtio-net-pci,netdev=guest20,mac=52:54:00:80:00:6f -netdev
> > type=tap,id=guest21,script=no,downscript=no,ifname=tap21,vnet_hdr
> > -device virtio-net-pci,netdev=guest21,mac=52:54:00:80:00:75 -serial
> > null  -parallel null  -m 496 -monitor tcp:0:4011,server,nowait -vnc :11
> > -qmp tcp:0:3011,server,nowait  -name 'gw-5000123'  -boot
> > order=nc,menu=on  -drive
> > index=2,media=cdrom,if=ide,cache=unsafe,aio=native,readonly=on  -k de
> > -incoming tcp:0:5011  -pidfile /var/run/qemu/vm-115.pid -mem-path
> > /hugepages  -mem-prealloc  -rtc base=utc -usb -usbdevice tablet -no-hpet
> > -vga vmware  -cpu qemu64
> First of all (but unrelated to the bug) do not use "-cpu qemu64" with KVM.

I remember there was an issue with kvm64 anytime in the past, but this
is  ages ago I think. I will change that for new vserver starts. What (which 
flag) is
the exact issue with qemu64 vs. kvm64

> Second, what downtime or bandwidth setting?  What is the actual
> downtime?  Can you print time.tsc_timestamp and migration_tsc on the
> destination?

From my logs:

migrate_set_speed 1200M
migrate_set_capability auto-converge on
migrate_set_capability xbzrle off

The max_downtime was default.

I will add debugging output around that assertion and try to reproduce.

Thank you,
Peter