From 1c20cf613b6919cb088908bbe2e7267f85581625 Mon Sep 17 00:00:00 2001
From: Adi Muraru <amuraru@adobe.com>
Date: Wed, 6 Oct 2021 00:01:35 +0300
Subject: [PATCH] Optionally configure envoy concurrency

---
 api/v1beta1/kafkacluster_types.go                |  9 +++++++++
 charts/kafka-operator/templates/crds.yaml        | 16 ++++++++++++++++
 .../crds/kafka.banzaicloud.io_kafkaclusters.yaml | 16 ++++++++++++++++
 pkg/resources/envoy/deployment.go                |  7 +++++++
 4 files changed, 48 insertions(+)

diff --git a/api/v1beta1/kafkacluster_types.go b/api/v1beta1/kafkacluster_types.go
index e67086b30..cbc94b623 100644
--- a/api/v1beta1/kafkacluster_types.go
+++ b/api/v1beta1/kafkacluster_types.go
@@ -238,6 +238,10 @@ type TopicConfig struct {
 type EnvoyConfig struct {
 	Image     string                       `json:"image,omitempty"`
 	Resources *corev1.ResourceRequirements `json:"resourceRequirements,omitempty"`
+	// Concurrency defines the number of worker threads envoy pod should run.
+	// If not specified defaults to the number of hardware threads on the underlying kubernetes node.
+	// +kubebuilder:validation:Minimum=1
+	Concurrency int32 `json:"concurrency,omitempty"`
 	// +kubebuilder:validation:Minimum=1
 	Replicas           int32                         `json:"replicas,omitempty"`
 	ServiceAccountName string                        `json:"serviceAccountName,omitempty"`
@@ -715,6 +719,11 @@ func (eConfig *EnvoyConfig) GetResources() *corev1.ResourceRequirements {
 	}
 }
 
+// GetConcurrency returns envoy concurrency
+func (eConfig *EnvoyConfig) GetConcurrency() int32 {
+	return eConfig.Concurrency
+}
+
 // GetResources returns the CC specific Kubernetes resource
 func (cConfig *CruiseControlConfig) GetResources() *corev1.ResourceRequirements {
 	if cConfig.Resources != nil {
diff --git a/charts/kafka-operator/templates/crds.yaml b/charts/kafka-operator/templates/crds.yaml
index b9cc78d59..ef52b2d58 100644
--- a/charts/kafka-operator/templates/crds.yaml
+++ b/charts/kafka-operator/templates/crds.yaml
@@ -15778,6 +15778,13 @@ spec:
                     description: Annotations defines the annotations placed on the
                       envoy ingress controller deployment
                     type: object
+                  concurrency:
+                    description: Concurrency defines the number of worker threads
+                      envoy pod should run. If not specified defaults to the number
+                      of hardware threads on the underlying kubernetes node.
+                    format: int32
+                    minimum: 1
+                    type: integer
                   disruptionBudget:
                     description: DisruptionBudget is the pod disruption budget attached
                       to Envoy Deployment(s)
@@ -17588,6 +17595,15 @@ spec:
                                         description: Annotations defines the annotations
                                           placed on the envoy ingress controller deployment
                                         type: object
+                                      concurrency:
+                                        description: Concurrency defines the number
+                                          of worker threads envoy pod should run.
+                                          If not specified defaults to the number
+                                          of hardware threads on the underlying kubernetes
+                                          node.
+                                        format: int32
+                                        minimum: 1
+                                        type: integer
                                       disruptionBudget:
                                         description: DisruptionBudget is the pod disruption
                                           budget attached to Envoy Deployment(s)
diff --git a/config/base/crds/kafka.banzaicloud.io_kafkaclusters.yaml b/config/base/crds/kafka.banzaicloud.io_kafkaclusters.yaml
index 157407fc8..7ed6d2168 100644
--- a/config/base/crds/kafka.banzaicloud.io_kafkaclusters.yaml
+++ b/config/base/crds/kafka.banzaicloud.io_kafkaclusters.yaml
@@ -15777,6 +15777,13 @@ spec:
                     description: Annotations defines the annotations placed on the
                       envoy ingress controller deployment
                     type: object
+                  concurrency:
+                    description: Concurrency defines the number of worker threads
+                      envoy pod should run. If not specified defaults to the number
+                      of hardware threads on the underlying kubernetes node.
+                    format: int32
+                    minimum: 1
+                    type: integer
                   disruptionBudget:
                     description: DisruptionBudget is the pod disruption budget attached
                       to Envoy Deployment(s)
@@ -17587,6 +17594,15 @@ spec:
                                         description: Annotations defines the annotations
                                           placed on the envoy ingress controller deployment
                                         type: object
+                                      concurrency:
+                                        description: Concurrency defines the number
+                                          of worker threads envoy pod should run.
+                                          If not specified defaults to the number
+                                          of hardware threads on the underlying kubernetes
+                                          node.
+                                        format: int32
+                                        minimum: 1
+                                        type: integer
                                       disruptionBudget:
                                         description: DisruptionBudget is the pod disruption
                                           budget attached to Envoy Deployment(s)
diff --git a/pkg/resources/envoy/deployment.go b/pkg/resources/envoy/deployment.go
index d8dc6a01f..fea84d1d2 100644
--- a/pkg/resources/envoy/deployment.go
+++ b/pkg/resources/envoy/deployment.go
@@ -18,6 +18,7 @@ import (
 	"crypto/sha256"
 	"encoding/hex"
 	"fmt"
+	"strconv"
 
 	"github.com/go-logr/logr"
 	"k8s.io/apimachinery/pkg/runtime"
@@ -65,6 +66,11 @@ func (r *Reconciler) deployment(log logr.Logger, extListener v1beta1.ExternalLis
 		},
 	}
 
+	arguments := []string{"-c", "/etc/envoy/envoy.yaml"}
+	if ingressConfig.EnvoyConfig.GetConcurrency() > 0 {
+		arguments = append(arguments, "--concurrency", strconv.Itoa(int(ingressConfig.EnvoyConfig.GetConcurrency())))
+	}
+
 	return &appsv1.Deployment{
 		ObjectMeta: templates.ObjectMetaWithAnnotations(
 			deploymentName,
@@ -92,6 +98,7 @@ func (r *Reconciler) deployment(log logr.Logger, extListener v1beta1.ExternalLis
 						{
 							Name:  "envoy",
 							Image: ingressConfig.EnvoyConfig.GetEnvoyImage(),
+							Args:  arguments,
 							Ports: append(exposedPorts,
 								[]corev1.ContainerPort{
 									{