diff --git a/docs/troubleshooting/windows-pv-tools.md b/docs/troubleshooting/windows-pv-tools.md index aea3c3e6..6378947d 100644 --- a/docs/troubleshooting/windows-pv-tools.md +++ b/docs/troubleshooting/windows-pv-tools.md @@ -188,3 +188,19 @@ See the [XenClean guide](/vms/#fully-removing-xen-pv-drivers-with-xenclean) for :::note You will need to reinstall the management agent. ::: + +## Windows Server 2025 hangs randomly with 0% CPU + +### Cause + +This can be due to the Viridian synthetic timer feature being disabled on the guest. + +### Solution + +First, check that [Viridian extensions are all enabled on your VM](/vms/#enabling-viridian-extensions). +If you've set boot parameters to disable the synthetic timer, they need to be reverted: + +``` +bcdedit /deletevalue "{current}" useplatformclock +bcdedit /deletevalue "{current}" useplatformtick +``` diff --git a/docs/vms/vms.md b/docs/vms/vms.md index 9a5ffa48..64501c88 100644 --- a/docs/vms/vms.md +++ b/docs/vms/vms.md @@ -340,20 +340,15 @@ Viridian extensions —referred to as "Viridian enlightenments" by Microsoft— Viridian enlightenments are enabled by default on Windows VM templates included with XCP-ng. -To enable Viridian enlightenments for other non-Windows VM templates, you need to: - -1. **Enable Viridian**. To do this, run `xe vm-param-set uuid= platform:viridian=true` in your VM. -2. **Enable the extra Viridian parameters** necessary for your template to run optimally with Windows. To do this, run the same `xe` command in your VM, but change the arguments with the following: - - ``` - "device_id": "0002", // ID used by XCP-ng to detect Windows VMs - "viridian": "true", - "viridian_time_ref_count": "true", - "viridian_reference_tsc": "true", - "viridian_apic_assist": "true", - "viridian_crash_ctl": "true", - "viridian_stimer": "true" - ``` +To enable Viridian enlightenments for other non-Windows VM templates, simply run the following command: + +``` +xe vm-param-set uuid= platform:device_id=0002 platform:viridian=true platform:viridian_time_ref_count=true platform:viridian_reference_tsc=true platform:viridian_apic_assist=true platform:viridian_crash_ctl=true platform:viridian_stimer=true +``` + +:::warning +Do not set the device ID on VMs with Xen PV drivers installed. Changing the device ID may cause old Xen PV drivers to fail booting. +::: :::