docs(create-windows-vm): disk bus guidance (virtio-blk default) and Hyper-V enlightenments - #1076
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docs(create-windows-vm): disk bus guidance (virtio-blk default) and Hyper-V enlightenments#1076abonillabeeche wants to merge 9 commits into
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…tenments Update the Volumes tab guidance to recommend the SCSI bus (virtio-scsi) for Windows workloads that do sustained writes; virtio-scsi supports multiple queues and has a more efficient DISCARD path than virtio-blk. Clarify that the Cloud Config field is processed on Windows images that include Cloudbase-Init (rather than being ignored outright). Note that after VMDP is installed the network model can be switched from e1000 to virtio for better throughput. Add a new "Recommended Tuning" section documenting KubeVirt's Hyper-V TLFS enlightenments as a suggested performance tuning for Windows guests, with the full YAML block and a verification command. Signed-off-by: Alejandro Bonilla <abonilla@suse.com>
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Co-authored-by: Jillian Maroket <67180770+jillian-maroket@users.noreply.github.com> Signed-off-by: Alejandro Bonilla <abonilla@suse.com>
Co-authored-by: Jillian Maroket <67180770+jillian-maroket@users.noreply.github.com> Signed-off-by: Alejandro Bonilla <abonilla@suse.com>
Co-authored-by: Jillian Maroket <67180770+jillian-maroket@users.noreply.github.com> Signed-off-by: Alejandro Bonilla <abonilla@suse.com>
Co-authored-by: Jillian Maroket <67180770+jillian-maroket@users.noreply.github.com> Signed-off-by: Alejandro Bonilla <abonilla@suse.com>
Co-authored-by: Jillian Maroket <67180770+jillian-maroket@users.noreply.github.com> Signed-off-by: Alejandro Bonilla <abonilla@suse.com>
Co-authored-by: Jillian Maroket <67180770+jillian-maroket@users.noreply.github.com> Signed-off-by: Alejandro Bonilla <abonilla@suse.com>
Co-authored-by: Jillian Maroket <67180770+jillian-maroket@users.noreply.github.com> Signed-off-by: Alejandro Bonilla <abonilla@suse.com>
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| 3. `StorageClass`: You can use the default StorageClass `harvester-longhorn` or specify a custom one. | ||
| 4. `Size`: The value `32` is set by default. See the disk space requirements for [Windows Server](https://docs.microsoft.com/en-us/windows-server/get-started/hardware-requirements#storage-controller-and-disk-space-requirements) and [Windows 11](https://docs.microsoft.com/en-us/windows/whats-new/windows-11-requirements#hardware-requirements) before changing this value. | ||
| 5. `Bus`: The value `VirtIO` is set by default. You can keep it or change it to the other available options, `SATA` or `SCSI`. | ||
| 5. `Bus`: The default value is `VirtIO`. For Windows workloads that generate sustained writes (such as large file copies, database write-ahead logs, and backup targets), `SCSI` (`virtio-scsi`) generally outperforms `VirtIO` (`virtio-blk`) because it supports multiple queues and uses a more efficient `DISCARD` path. `SATA` is a secondary option for scenarios where paravirtualized drivers cannot be loaded at boot time. |
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I am curious about this one, since Kubevirt did not support SCSI with multiple queues.
I need to check... Or do we have any reference for it?
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Reverted to VirtIO.
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…e disk bus Benchmarks on Harvester + LVM CSI (Windows Server 2022, Hyper-V enlightenments enabled to isolate the bus) show virtio-blk matches virtio-scsi on sequential/random-read and delivers ~2x the IOPS at about half the latency on random-write and mixed workloads. Update the Bus guidance to recommend virtio-blk as the default and position virtio-scsi as the choice for many-disks-per-controller and SCSI features (UNMAP/ DISCARD passthrough, persistent reservations). Applies to current docs and the v1.8 versioned copy, matching harvester/harvester#11127. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Signed-off-by: Alejandro Bonilla <abonilla@suse.com>
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…r#1076 The disk-bus and Hyper-V enlightenment guidance for create-windows-vm.md lives in harvester#1076. Remove the duplicated copy here so this PR is scoped solely to Resource Overcommit defaults and the Virtual Machines landing-page pointer, per review feedback. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Signed-off-by: Alejandro Bonilla <abonilla@suse.com>
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Summary
Adds guidance to the Windows VM creation documentation on three areas that operators typically need to configure by hand today:
Bus— recommendSCSI(virtio-scsi) for Windows workloads that do sustained writes. virtio-scsi supports multiple queues and has a more efficient DISCARD path than virtio-blk.SATAremains a compatible fallback.Cloud Config— clarify that this field IS processed on Windows images that ship with Cloudbase-Init. The previous wording ("not applied to Windows-based VMs") was too broad.Model— note thate1000is a safe default while paravirtualized drivers are still being installed, and that switching tovirtioafter VMDP is loaded gives higher throughput and lower CPU overhead.Adds a new Recommended Tuning section before Known Issues documenting how to enable KubeVirt's Hyper-V TLFS enlightenments on Windows guests, with the full YAML block and a verification command. This is a well-known Windows-on-KVM tuning that most people rediscover the hard way; documenting it in the VM creation page surfaces it at the right moment.
Same content is applied to both:
Notes
Documentation-only. No behavior changes.