docs(vm): correct overcommit defaults and warn about aggressive CPU ratio

docs/vm/resource-overcommit.md

@@ -18,16 +18,22 @@ Harvester supports global configuration of resource overload percentages on CPU,
 
 Harvester allows you to overcommit CPU and RAM on compute nodes. This allows you to increase the number of instances running on your cloud at the cost of reducing the performance of the instances. The Compute service uses the following ratios by default:
 
-- CPU allocation ratio: 1600%
+- CPU allocation ratio: 1000%
 - RAM allocation ratio: 150%
-- Storage allocation ratio: 200%
+- Storage allocation ratio: 100%
 
 :::note
 
 Classic memory overcommitment or memory ballooning is not yet supported by this feature. In other words, memory used by a virtual machine instance cannot be returned once allocated.
 
 :::
 
+:::info important
+
+The default CPU allocation ratio of 1000% is aggressive, treating each host CPU as 10 vCPUs. Under heavy workloads, this ratio can cause significant CPU steal time and performance degradation. Consider lowering this ratio for latency-sensitive or sustained CPU-bound workloads (such as databases, real-time services, and interactive Windows desktops). A conservative starting point is 200 to 400% based on benchmarking results under realistic loads.
+
+:::
+
 ## Configure the global setting [`overcommit-config`](../advanced/settings.md#overcommit-config)
 
 Users can modify the global `overcommit-config` by following the steps below, and it will be applied to each newly created virtual machine after the change.

docs/vm/virtual-machines.md

@@ -20,7 +20,13 @@ You can create [Linux VMs](../vm/create-vm.md) using one of the following method
 - Kubernetes API: Create a `VirtualMachine` object. 
 - [Harvester Terraform Provider](../terraform/terraform-provider.md): Define a `harvester_virtualmachine` resource block. 
 
-Creating [Windows VMs](../vm/create-windows-vm.md) on the Harvester UI involves slightly different steps. Harvester provides a VM template named `windows-iso-image-base-template` that adds a volume with the Virtio drivers for Windows, which streamlines the VM configuration process. If you require Virtio devices but choose to not use the template, you must add your own Virtio drivers for Windows to enable correct hardware detection. 
+Creating [Windows VMs](../vm/create-windows-vm.md) on the Harvester UI involves slightly different steps. Harvester provides a VM template named `windows-iso-image-base-template` that adds a volume with the Virtio drivers for Windows, which streamlines the VM configuration process. If you require Virtio devices but choose to not use the template, you must add your own Virtio drivers for Windows to enable correct hardware detection.
+
+:::note
+
+Before creating virtual machines, review [Resource Overcommit](../vm/resource-overcommit.md) and verify that the cluster's default CPU, memory, and storage allocation ratios match your workload requirements. The default values suit dense, general-purpose workloads but may be too aggressive for latency-sensitive or CPU-bound guests.
+
+:::
 
 ## Validated Guest Operating Systems
 

versioned_docs/version-v1.8/vm/resource-overcommit.md

@@ -18,16 +18,22 @@ Harvester supports global configuration of resource overload percentages on CPU,
 
 Harvester allows you to overcommit CPU and RAM on compute nodes. This allows you to increase the number of instances running on your cloud at the cost of reducing the performance of the instances. The Compute service uses the following ratios by default:
 
-- CPU allocation ratio: 1600%
+- CPU allocation ratio: 1000%
 - RAM allocation ratio: 150%
-- Storage allocation ratio: 200%
+- Storage allocation ratio: 100%
 
 :::note
 
 Classic memory overcommitment or memory ballooning is not yet supported by this feature. In other words, memory used by a virtual machine instance cannot be returned once allocated.
 
 :::
 
+:::note
+
+The default CPU allocation ratio of 1000% is aggressive: a host CPU is treated as if it provides 10 vCPUs. Under load, this can produce noticeable CPU steal and latency spikes in guests. For workloads that are latency-sensitive or perform sustained CPU-bound work (for example, databases, real-time services, or interactive Windows desktops), benchmark with a representative workload and reduce the CPU allocation ratio if you observe degradation. A common conservative starting point is 200–400%.
+
+:::
+
 ## Configure the global setting [`overcommit-config`](../advanced/settings.md#overcommit-config)
 
 Users can modify the global `overcommit-config` by following the steps below, and it will be applied to each newly created virtual machine after the change.

versioned_docs/version-v1.8/vm/virtual-machines.md

@@ -20,7 +20,13 @@ You can create [Linux VMs](../vm/create-vm.md) using one of the following method
 - Kubernetes API: Create a `VirtualMachine` object. 
 - [Harvester Terraform Provider](../terraform/terraform-provider.md): Define a `harvester_virtualmachine` resource block. 
 
-Creating [Windows VMs](../vm/create-windows-vm.md) on the Harvester UI involves slightly different steps. Harvester provides a VM template named `windows-iso-image-base-template` that adds a volume with the Virtio drivers for Windows, which streamlines the VM configuration process. If you require Virtio devices but choose to not use the template, you must add your own Virtio drivers for Windows to enable correct hardware detection. 
+Creating [Windows VMs](../vm/create-windows-vm.md) on the Harvester UI involves slightly different steps. Harvester provides a VM template named `windows-iso-image-base-template` that adds a volume with the Virtio drivers for Windows, which streamlines the VM configuration process. If you require Virtio devices but choose to not use the template, you must add your own Virtio drivers for Windows to enable correct hardware detection.
+
+:::note
+
+Before creating virtual machines, review [Resource Overcommit](../vm/resource-overcommit.md) to confirm that the cluster's default CPU, memory, and storage allocation ratios match your workload requirements. The defaults suit dense general-purpose workloads but may be too aggressive for latency-sensitive or CPU-bound guests.
+
+:::
 
 ## Validated Guest Operating Systems