Thanks you, Yes, indeed after virsh start. That's will surely help. I am really struggling to understand how eventually the libvirt is managing the qemu via its fd's I can see that virsh is launching qemu right after: execve(binary, cmd->args, cmd->env); I have grasp too that libvirtd is communicate with the qemu through. virCgroupSetValueStr (group=0x7fb87400cd10, controller=0, key=0x7fb8b4377bbb "tasks", value=0x7fb874008170 "6909") at util/vircgroup.c:751 5: value = 0x7fb874008170 "6909" 1: keypath = 0x7fb87400ecd0 "/sys/fs/cgroup/cpu,cpuacct/machine/VBS2.libvirt-qemu/vcpu0/tasks" Where value is the thread running the VCPU. Thread 0x7fa684833700 (LWP 6909) "qemu-system-x86" pthread_cond_wait@@GLIBC_2.3.2 () Another example is setting the env parameter. virCgroupSetValueStr (group=0x7fb87400cd10, controller=2, key=0x7fb8b43779eb "cpuset.cpus", value=0x7fb874010dd0 "0-15") at util/vircgroup.c:751 5: value = 0x7fb874010dd0 "0-15" 1: keypath = 0x7fb87400ecd0 "/sys/fs/cgroup/cpuset/machine/VBS2.libvirt-qemu/vcpu0/cpuset.cpus" I have failed to get Cgroup idea And to actually see my event being traced. Thanks for your quick response. Very appreciated. Regards, Nir -----Original Message----- From: Martin Kletzander [mailto:mkletzan@xxxxxxxxxx] Sent: Thursday, July 14, 2016 9:00 AM To: Nir Levy <nirl@xxxxxxxxxxxxxxxxx> Cc: libvir-list@xxxxxxxxxx; veillard@xxxxxxxxxx Subject: Re: Disconnected from qemu, keepalive timeout On Wed, Jul 13, 2016 at 03:47:37PM +0000, Nir Levy wrote: >Hello Guys, > >Thanks for reading this, >I have compiled libvirt and qemu over fedora 22 for using debug information and no opt ("-g3 -O0"). >I am investigating the xml feature > <qemu:commandline> > <qemu:arg value='-trace'/> > <qemu:arg value='events=/home/qemu_traced_symbols'/> > </qemu:commandline> > >qemu_traced_symbols includes all qemu traced symbols. > >I have used: >catch syscall clone >set follow-fork-mode child >set detach-on-fork off > >and debugged the child >so after libvirt start VM2 wanted to debug the parameters (cmd->args, >which indeed includes -trace and events=/home/qemu_traced_symbols I have debugged the the child after spawning. >And returned for the parent (using gdb inferior 1) for debugging the >virCommandHandshakeWait (with the args) > >but I keep getting >error: Disconnected from qemu:///system due to keepalive timeout grep @ >libvirt-1.2.21/ shows no code only change log. > You are getting this from the 'virsh start $domain' command, right? >Can you please help me resolve this issue? >How do those args are passed, is it via JSON? > For your use case you really want to disable the keepalive by using -k0 parameter for virsh, so it will become 'virsh -k0 start $domain' >Kind regards, >Nir Levy >SW Engineer > >Web: www.asocstech.com<http://www.asocstech.com/> | >[cid:image001.jpg@01D1B599.5A2C9530] > >-- >libvir-list mailing list >libvir-list@xxxxxxxxxx >https://www.redhat.com/mailman/listinfo/libvir-list -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list