Hi all, I have a problem with libvirt, it works slow. For example, "virsh list" takes 6..7 seconds. I found this in libvirt log: ... 11:38:12.765: debug : virEventDispatchHandles:477 : Dispatch n=8 f=56 w=9 e=1 0x25ce830 11:38:12.765: debug : virEventUpdateHandleImpl:147 : Update handle w=8 e=3 11:38:12.765: debug : virEventInterruptLocked:668 : Interrupting 11:38:12.766: debug : xenStoreDomainIntroduced:1421 : Some domains were missing, trying again 11:38:12.867: debug : xenStoreDomainIntroduced:1421 : Some domains were missing, trying again 11:38:12.968: debug : xenStoreDomainIntroduced:1421 : Some domains were missing, trying again (about 20 such entries) 11:38:14.681: debug : xenStoreDomainIntroduced:1421 : Some domains were missing, trying again 11:38:14.782: debug : virEventDispatchHandles:464 : i=9 w=10 11:38:14.782: debug : virEventCleanupTimeouts:495 : Cleanup 3 11:38:14.782: debug : virEventCleanupHandles:536 : Cleanupo 10 ... That''s my time spent. Now look at xenstored config (via script from http://wiki.xensource.com/xenwiki/XenStore) /vm/00000000-0000-0000-0000-000000000000/on_xend_stop=ignore /vm/00000000-0000-0000-0000-000000000000/shadow_memory=0 /vm/00000000-0000-0000-0000-000000000000/uuid=00000000-0000-0000-0000-000000000000 /vm/00000000-0000-0000-0000-000000000000/on_reboot=restart /vm/00000000-0000-0000-0000-000000000000/image/ostype=linux /vm/00000000-0000-0000-0000-000000000000/image/kernel/vm/00000000-0000-0000-0000-000000000000/image/cmdline/vm/00000000-0000-0000-0000-000000000000/image/ramdisk/vm/00000000-0000-0000-0000-000000000000/on_poweroff=destroy /vm/00000000-0000-0000-0000-000000000000/bootloader_args/vm/00000000-0000-0000-0000-000000000000/on_xend_start=ignore /vm/00000000-0000-0000-0000-000000000000/on_crash=restart /vm/00000000-0000-0000-0000-000000000000/xend/restart_count=0 /vm/00000000-0000-0000-0000-000000000000/vcpus=4 /vm/00000000-0000-0000-0000-000000000000/vcpu_avail=15 /vm/00000000-0000-0000-0000-000000000000/bootloader/vm/00000000-0000-0000-0000-000000000000/name=Domain-0 /vm/00000000-0000-0000-0000-000000000000-1/on_xend_stop=ignore /vm/00000000-0000-0000-0000-000000000000-1/shadow_memory=0 /vm/00000000-0000-0000-0000-000000000000-1/uuid=00000000-0000-0000-0000-000000000000 /vm/00000000-0000-0000-0000-000000000000-1/on_reboot=restart /vm/00000000-0000-0000-0000-000000000000-1/image/ostype=linux /vm/00000000-0000-0000-0000-000000000000-1/image/kernel/vm/00000000-0000-0000-0000-000000000000-1/image/cmdline/vm/00000000-0000-0000-0000-000000000000-1/image/ramdisk/vm/00000000-0000-0000-0000-000000000000-1/on_poweroff=destroy /vm/00000000-0000-0000-0000-000000000000-1/bootloader_args/vm/00000000-0000-0000-0000-000000000000-1/on_xend_start=ignore /vm/00000000-0000-0000-0000-000000000000-1/on_crash=restart /vm/00000000-0000-0000-0000-000000000000-1/xend/restart_count=0 /vm/00000000-0000-0000-0000-000000000000-1/vcpus=4 /vm/00000000-0000-0000-0000-000000000000-1/vcpu_avail=15 /vm/00000000-0000-0000-0000-000000000000-1/bootloader/vm/00000000-0000-0000-0000-000000000000-1/name=Domain-0 /local/domain/0/vm=/vm/00000000-0000-0000-0000-000000000000-1 /local/domain/0/device... I have two (sometimes more) "Domain-0" vms. I think every reboot adds a new one. I run "xenstore-rm /vm/00000000-0000-0000-0000-000000000000", "xenstore-rm /vm/00000000-0000-0000-0000-000000000000-1" and so on for every entry. After reboot I have one "Domain-0" and "virsh list" takes 0,4 second until next reboot. Part of xend.log (reboot):: [2012-03-21 12:17:51 1768] INFO (SrvDaemon:220) Xend exited with status 0. [2012-03-21 12:20:53 1791] INFO (SrvDaemon:332) Xend Daemon started [2012-03-21 12:20:53 1791] INFO (SrvDaemon:336) Xend changeset: unavailable. [2012-03-21 12:20:55 1791] DEBUG (XendDomainInfo:149) XendDomainInfo.recreate({''max_vcpu_id'': 3, ''cpu_time'': 10554784758L, ''ssidref'': 0, ''hvm'': 0, ''shutdown_reason'': 255, ''dying'': 0, ''online_vcpus'': 4, ''domid'': 0, ''paused'': 0, ''crashed'': 0, ''running'': 1, ''maxmem_kb'': 17179869180L, ''shutdown'': 0, ''mem_kb'': 3400960L, ''handle'': [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], ''blocked'': 0, ''name'': ''Domain-0''}) [2012-03-21 12:20:55 1791] INFO (XendDomainInfo:167) Recreating domain 0, UUID 00000000-0000-0000-0000-000000000000. at /local/domain/0 [2012-03-21 12:20:55 1791] DEBUG (XendDomainInfo:3400) Storing VM details: {''on_xend_stop'': ''ignore'', ''shadow_memory'': ''0'', ''uuid'': ''00000000-0000-0000-0000-000000000000'', ''on_reboot'': ''restart'', ''image'': ''(linux (kernel ) (superpages 0) (tsc_mode 0) (nomigrate 0))'', ''on_poweroff'': ''destroy'', ''bootloader_args'': '''', ''on_xend_start'': ''ignore'', ''on_crash'': ''restart'', ''xend/restart_count'': ''0'', ''vcpus'': ''4'', ''vcpu_avail'': ''15'', ''bootloader'': '''', ''name'': ''Domain-0''} [2012-03-21 12:20:55 1791] DEBUG (XendDomainInfo:1804) Storing domain details: {''cpu/3/availability'': ''online'', ''description'': '''', ''console/limit'': ''1048576'', ''memory/target'': ''3400960'', ''cpu/2/availability'': ''online'', ''vm'': ''/vm/00000000-0000-0000-0000-000000000000-1'', ''domid'': ''0'', ''cpu/0/availability'': ''online'', ''cpu/1/availability'': ''online'', ''control/platform-feature-multiprocessor-suspend'': ''1'', ''console/type'': ''xenconsoled'', ''name'': ''Domain-0''} [2012-03-21 12:20:55 1791] DEBUG (XendDomain:464) Adding Domain: 0 [2012-03-21 12:20:55 1791] DEBUG (XendDomain:398) number of vcpus to use is 0 [2012-03-21 12:20:55 1791] DEBUG (XendDomainInfo:1891) XendDomainInfo.handleShutdownWatch [2012-03-21 12:20:55 1791] INFO (SrvServer:177) unix path=/var/lib/xend/xend-socket ... Why xen creates a new vm "Domain-0" instead of using an existing one? Is it a bug? How can it be fixed? My software: root@sl03500008180:~# dpkg -l | grep xen ii libxenstore3.0 4.0.1-4 Xenstore communications library for Xen ii linux-image-2.6.32-5-xen-amd64 2.6.32-41 Linux 2.6.32 for 64-bit PCs, Xen dom0 support ii xen-hypervisor-4.0-amd64 4.0.1-4 The Xen Hypervisor on AMD64 ii xen-linux-system-2.6-xen-amd64 2.6.32+29 Xen system with Linux 2.6 for 64-bit PCs (meta-package) ii xen-linux-system-2.6.32-5-xen-amd64 2.6.32-41 Xen system with Linux 2.6.32 on 64-bit PCs (meta-package) ii xen-qemu-dm-4.0 4.0.1-2 Xen Qemu Device Model virtual machine hardware emulator ii xen-utils-4.0 4.0.1-4 XEN administrative tools ii xen-utils-common 4.0.0-1 XEN administrative tools - common files ii xenstore-utils 4.0.1-4 Xenstore utilities for Xen root@sl03500008180:~# lsb_release -a No LSB modules are available. Distributor ID: Debian Description: Debian GNU/Linux 6.0.4 (squeeze) Release: 6.0.4 Codename: squeeze root@sl03500008180:~# uname -a Linux sl03500008180.opfr.local 2.6.32-5-xen-amd64 #1 SMP Mon Jan 16 20:48:30 UTC 2012 x86_64 GNU/Linux Regards, Dmitry