feat(ocean): autoscaler configuration (#19)

Co-authored-by: Bharat Kumar Govindaradjou <bgovindaradjou@ip-192-168-0-7.eu-west-1.compute.internal>

ocean.tf

@@ -37,10 +37,37 @@ EOF
     key   = "kubernetes.io/cluster/${local.cluster_name}"
     value = "owned"
   }
-
+  
   autoscaler {
-    autoscale_is_enabled     = true
-    autoscale_is_auto_config = true
+    autoscale_is_enabled     = var.autoscale_is_enabled
+    autoscale_is_auto_config = var.autoscale_is_enabled
+    auto_headroom_percentage = var.autoscaler_headroom_percentage
+    autoscale_cooldown       = var.autoscaler_cooldown
+
+    dynamic "autoscale_headroom" {
+      for_each = var.autoscale_is_enabled && var.autoscaler_cpu_per_unit != null && var.autoscaler_memory_per_unit != null && var.autoscaler_num_of_units != null && var.autoscaler_gpu_per_unit != null ? [1] : []
+      content {
+        cpu_per_unit    = var.autoscaler_cpu_per_unit
+        gpu_per_unit    = var.autoscaler_gpu_per_unit
+        memory_per_unit = var.autoscaler_memory_per_unit
+        num_of_units    = var.autoscaler_num_of_units
+      }
+    }
+
+    dynamic "autoscale_down" {
+      for_each = var.autoscale_is_enabled && var.autoscaler_max_scale_down_percentage != null ? [1] : []
+      content {
+        max_scale_down_percentage = var.autoscaler_max_scale_down_percentage
+      }
+    }
+
+    dynamic "resource_limits" {
+      for_each = var.autoscale_is_enabled && var.autoscaler_max_vcpu != null && var.autoscaler_max_memory_gib != null ? [1] : []
+      content {
+        max_vcpu       = var.autoscaler_max_vcpu
+        max_memory_gib = var.autoscaler_max_memory_gib
+      }
+    }
   }
 
   dynamic "update_policy" {

variables.tf

@@ -514,6 +514,66 @@ variable "spot_percentage" {
   default     = 100
 }
 
+variable "autoscale_is_enabled" {
+  type        = bool
+  description = "Enables/disables the Ocean Kubernetes Auto Scaler. Default is true"
+  default     = true
+}
+
+variable "autoscaler_headroom_percentage" {
+  type        = number
+  description = "Sets the auto headroom percentage (a number in the range [0, 200]) which controls the percentage of headroom from the cluster. Relevant only when autoscale_is_auto_config toggled on"
+  default     = null
+}
+
+variable "autoscaler_cooldown" {
+  type        = number
+  description = "Sets cooldown period between scaling actions"
+  default     = null
+}
+
+variable "autoscaler_cpu_per_unit" {
+  type        = number
+  description = "Configures the number of CPUs to allocate the headroom. CPUs are denoted in millicores, where 1000 millicores = 1 vCPU"
+  default     = null
+}
+
+variable "autoscaler_gpu_per_unit" {
+  type        = number
+  description = "Configures the number of GPUs to allocate the headroom"
+  default     = null
+}
+
+variable "autoscaler_memory_per_unit" {
+  type        = number
+  description = "Configures the amount of memory (MB) to allocate the headroom"
+  default     = null
+}
+
+variable "autoscaler_num_of_units" {
+  type        = number
+  description = "Sets the number of units to retain as headroom, where each unit has the defined headroom CPU and memory."
+  default     = null
+}
+
+variable "autoscaler_max_scale_down_percentage" {
+  type        = number
+  description = "Sets the maximum % to scale-down. Number between 1-100"
+  default     = null
+}
+
+variable "autoscaler_max_vcpu" {
+  type        = number
+  description = "Sets the maximum cpu in vCPU units that can be allocated to the cluster."
+  default     = null
+}
+
+variable "autoscaler_max_memory_gib" {
+  type        = number
+  description = "Sets the maximum memory in GiB units that can be allocated to the cluster"
+  default     = null
+}
+
 variable "update_policy" {
   type = object({
     should_roll           = bool