feat: Add advanced machine feature options for enabling virtualization and setting threads per core (#236)

Author: timstoop

examples/instance_template/simple/README.md

@@ -7,12 +7,14 @@ This is a simple, minimal example of how to use the instance_template module.
 
 | Name | Description | Type | Default | Required |
 |------|-------------|------|---------|:--------:|
+| enable\_nested\_virtualization | Defines whether the instance should have nested virtualization enabled. | `bool` | `false` | no |
 | labels | Labels, provided as a map | `map(string)` | n/a | yes |
 | project\_id | The GCP project to use for integration tests | `string` | n/a | yes |
 | region | The GCP region to create and test resources in | `string` | `"us-central1"` | no |
 | service\_account | Service account to attach to the instance. See https://www.terraform.io/docs/providers/google/r/compute_instance_template.html#service_account. | <pre>object({<br>    email  = string<br>    scopes = set(string)<br>  })</pre> | `null` | no |
 | subnetwork | The name of the subnetwork create this instance in. | `string` | `""` | no |
 | tags | Network tags, provided as a list | `list(string)` | n/a | yes |
+| threads\_per\_core | The number of threads per physical core. To disable simultaneous multithreading (SMT) set this to 1. | `string` | `null` | no |
 
 ## Outputs
 

examples/instance_template/simple/main.tf

@@ -32,12 +32,14 @@ locals {
 }
 
 module "instance_template" {
-  source          = "../../../modules/instance_template"
-  project_id      = var.project_id
-  subnetwork      = var.subnetwork
-  service_account = var.service_account
-  name_prefix     = "simple"
-  tags            = var.tags
-  labels          = var.labels
-  access_config   = [local.access_config]
+  source                       = "../../../modules/instance_template"
+  project_id                   = var.project_id
+  subnetwork                   = var.subnetwork
+  service_account              = var.service_account
+  name_prefix                  = "simple"
+  tags                         = var.tags
+  labels                       = var.labels
+  access_config                = [local.access_config]
+  enable_nested_virtualization = var.enable_nested_virtualization
+  threads_per_core             = var.threads_per_core
 }

examples/instance_template/simple/variables.tf

@@ -51,3 +51,14 @@ variable "labels" {
   description = "Labels, provided as a map"
 }
 
+variable "enable_nested_virtualization" {
+  type        = bool
+  description = "Defines whether the instance should have nested virtualization enabled."
+  default     = false
+}
+
+variable "threads_per_core" {
+  type        = string
+  description = "The number of threads per physical core. To disable simultaneous multithreading (SMT) set this to 1."
+  default     = null
+}

modules/instance_template/README.md

@@ -24,6 +24,7 @@ See the [simple](../../examples/instance_template/simple) for a usage example.
 | disk\_size\_gb | Boot disk size in GB | `string` | `"100"` | no |
 | disk\_type | Boot disk type, can be either pd-ssd, local-ssd, or pd-standard | `string` | `"pd-standard"` | no |
 | enable\_confidential\_vm | Whether to enable the Confidential VM configuration on the instance. Note that the instance image must support Confidential VMs. See https://cloud.google.com/compute/docs/images | `bool` | `false` | no |
+| enable\_nested\_virtualization | Defines whether the instance should have nested virtualization enabled. | `bool` | `false` | no |
 | enable\_shielded\_vm | Whether to enable the Shielded VM configuration on the instance. Note that the instance image must support Shielded VMs. See https://cloud.google.com/compute/docs/images | `bool` | `false` | no |
 | gpu | GPU information. Type and count of GPU to attach to the instance template. See https://cloud.google.com/compute/docs/gpus more details | <pre>object({<br>    type  = string<br>    count = number<br>  })</pre> | `null` | no |
 | labels | Labels, provided as a map | `map(string)` | `{}` | no |
@@ -46,6 +47,7 @@ See the [simple](../../examples/instance_template/simple) for a usage example.
 | subnetwork | The name of the subnetwork to attach this interface to. The subnetwork must exist in the same region this instance will be created in. Either network or subnetwork must be provided. | `string` | `""` | no |
 | subnetwork\_project | The ID of the project in which the subnetwork belongs. If it is not provided, the provider project is used. | `string` | `""` | no |
 | tags | Network tags, provided as a list | `list(string)` | `[]` | no |
+| threads\_per\_core | The number of threads per physical core. To disable simultaneous multithreading (SMT) set this to 1. | `any` | `null` | no |
 
 ## Outputs
 

modules/instance_template/main.tf

@@ -148,6 +148,11 @@ resource "google_compute_instance_template" "tpl" {
     on_host_maintenance = local.on_host_maintenance
   }
 
+  advanced_machine_features {
+    enable_nested_virtualization = var.enable_nested_virtualization
+    threads_per_core             = var.threads_per_core
+  }
+
   dynamic "shielded_instance_config" {
     for_each = local.shielded_vm_configs
     content {

modules/instance_template/variables.tf

@@ -71,6 +71,17 @@ variable "region" {
   default     = null
 }
 
+variable "enable_nested_virtualization" {
+  type        = bool
+  description = "Defines whether the instance should have nested virtualization enabled."
+  default     = false
+}
+
+variable "threads_per_core" {
+  description = "The number of threads per physical core. To disable simultaneous multithreading (SMT) set this to 1."
+  default     = null
+}
+
 #######
 # disk
 #######