Increase the default PVC size for logstash

docs/orchestrating-elastic-stack-applications/logstash.asciidoc

@@ -301,7 +301,11 @@ WARNING: Volume support for Logstash is a breaking change to earlier versions of
 [discrete]
 == Specifying the volume claim settings
 
-By default, a PersistentVolume called `logstash-data` is created, that maps to `/usr/share/logstash/data` for persistent storage, typically used for storage from plugins. The `logstash-data` volume claim is, by default, a small (1Gi) volume, using the standard StorageClass of your Kubernetes cluster, but can be overridden by adding a `spec.volumeClaimTemplate` section named `logstash-data`.
+A PersistentVolume called `logstash-data` is created by default.
+It maps to `/usr/share/logstash/data` for persistent storage, which is typically used for storage from plugins. 
+
+By default, the `logstash-data` volume claim is a `1.5Gi` volume, using the standard StorageClass of your Kubernetes cluster. 
+You can override the default by adding a `spec.volumeClaimTemplate` section named `logstash-data`.
 
 For production workloads, you should define your own volume claim template with the desired storage capacity and (optionally) the Kubernetes link:https://kubernetes.io/docs/concepts/storage/storage-classes/[storage class] to associate with the persistent volume. To override this volume claim for `data` usages, the name of this volume claim must be `logstash-data`.
 
@@ -326,8 +330,15 @@ spec:
             storage: 2Gi
 ----
 
+The default volume size will likely be insufficient for production workloads, especially when you are using:
+
+* the persistent queue (PQ) feature
+* dead letter queues (DLQ), or 
+* {ls} plugins that make heavy use of temporary storage. 
+
+Increase the storage capacity, or consider creating separate volumes for these use cases.
 
-Separate storage, for example for Logstash configurations using persistent queues (PQ) and/or dead letter queues (DLQ), can be added by including an additional `spec.volumeClaimTemplate` along with a corresponding `spec.podTemplate.spec.containers.volumeMount` for each requested volume.
+You can add separate storage by including an additional `spec.volumeClaimTemplate` along with a corresponding `spec.podTemplate.spec.containers.volumeMount` for each requested volume.
 
 This example shows how to setup separate storage for a PQ:
 

pkg/controller/logstash/logstash_controller_test.go

@@ -191,7 +191,7 @@ func TestReconcileLogstash_Reconcile(t *testing.T) {
 									StorageClassName: ptr.To[string](sampleStorageClass.Name),
 									Resources: corev1.VolumeResourceRequirements{
 										Requests: corev1.ResourceList{
-											corev1.ResourceStorage: resource.MustParse("1Gi"),
+											corev1.ResourceStorage: resource.MustParse("1.5Gi"),
 										},
 									},
 								},
@@ -303,7 +303,7 @@ func TestReconcileLogstash_Reconcile(t *testing.T) {
 									StorageClassName: ptr.To[string](sampleStorageClass.Name),
 									Resources: corev1.VolumeResourceRequirements{
 										Requests: corev1.ResourceList{
-											corev1.ResourceStorage: resource.MustParse("1Gi"),
+											corev1.ResourceStorage: resource.MustParse("1.5Gi"),
 										},
 									},
 								},
@@ -432,7 +432,7 @@ func TestReconcileLogstash_Reconcile(t *testing.T) {
 									StorageClassName: ptr.To[string](sampleStorageClass.Name),
 									Resources: corev1.VolumeResourceRequirements{
 										Requests: corev1.ResourceList{
-											corev1.ResourceStorage: resource.MustParse("1Gi"),
+											corev1.ResourceStorage: resource.MustParse("1.5Gi"),
 										},
 									},
 								},
@@ -550,7 +550,7 @@ func TestReconcileLogstash_Reconcile(t *testing.T) {
 									StorageClassName: ptr.To[string](sampleStorageClass.Name),
 									Resources: corev1.VolumeResourceRequirements{
 										Requests: corev1.ResourceList{
-											corev1.ResourceStorage: resource.MustParse("1Gi"),
+											corev1.ResourceStorage: resource.MustParse("1.5Gi"),
 										},
 									},
 								},
@@ -650,15 +650,15 @@ func TestReconcileLogstash_Resize(t *testing.T) {
 	}{
 		{
 			name:            "Cannot increase storage with fixed storage class",
-			initialCapacity: "1Gi",
+			initialCapacity: "1.5Gi",
 			desiredCapacity: "3Gi",
 			storageClass:    fixedStorageClass,
 			wantErr:         true,
 		},
 		{
 			name:            "Cannot decrease storage with resizable storage class",
 			initialCapacity: "3Gi",
-			desiredCapacity: "1Gi",
+			desiredCapacity: "1.5Gi",
 			storageClass:    resizableStorageClass,
 			wantErr:         true,
 		},
@@ -671,14 +671,14 @@ func TestReconcileLogstash_Resize(t *testing.T) {
 		},
 		{
 			name:            "Nothing happens when keeping the storage the same with resizable storage class",
-			initialCapacity: "1Gi",
-			desiredCapacity: "1Gi",
+			initialCapacity: "1.5Gi",
+			desiredCapacity: "1.5Gi",
 			storageClass:    resizableStorageClass,
 			wantErr:         false,
 		},
 		{
 			name:            "Can successfully resize the storage with resizable storage class",
-			initialCapacity: "1Gi",
+			initialCapacity: "1.5Gi",
 			desiredCapacity: "3Gi",
 			storageClass:    resizableStorageClass,
 			extraVerify: func(r ReconcileLogstash, desiredCapacity string) (reconcile.Result, error) {

pkg/controller/logstash/volume/defaults.go

@@ -21,10 +21,10 @@ var (
 		ContainerMountPath:     ConfigMountPath,
 	}
 
-	DefaultPersistentVolumeSize = resource.MustParse("1Gi")
+	DefaultPersistentVolumeSize = resource.MustParse("1.5Gi")
 
 	// DefaultDataVolumeClaim is the default data volume claim for Logstash pods.
-	// We default to a 1GB persistent volume, using the default storage class.
+	// We default to a 1.5Gi persistent volume, using the default storage class.
 	DefaultDataVolumeClaim = corev1.PersistentVolumeClaim{
 		ObjectMeta: metav1.ObjectMeta{
 			Name: LogstashDataVolumeName,