Kevin Wolf <kw...@redhat.com> writes: > Am 24.10.2011 12:00, schrieb Chris Webb: > > I have qemu monitor access and can even strace the relevant qemu process if > > necessary: is it possible to use this to diagnose what's caused this guest > > to stop, e.g. the unsupported instruction if it's an emulation failure? > > Another common cause for stopped VMs are I/O errors, for example writes > to a sparse image when the disk is full.
This guest are backed by LVM LVs so I don't think they can return EFULL, but I could imagine read errors, so I've just done a trivial test to make sure I can read them end-to-end: 0015# dd if=/dev/mapper/guest\:e549f8e1-4c0e-4dea-826a-e4b877282c07\:ide\:0\:0 of=/dev/null bs=1M 3136+0 records in 3136+0 records out 3288334336 bytes (3.3 GB) copied, 20.898 s, 157 MB/s 0015# dd if=/dev/mapper/guest\:e549f8e1-4c0e-4dea-826a-e4b877282c07\:ide\:0\:1 of=/dev/null bs=1M 276+0 records in 276+0 records out 289406976 bytes (289 MB) copied, 1.85218 s, 156 MB/s Is there any way to ask qemu why a guest has stopped, so I can distinguish IO problems from emulation problems from anything else? Cheers, Chris.
