Add a flag to enable or disable aio_write (#10394)

* Add a flag to enable or disable aio_write

Signed-off-by: z1cheng <imchench@gmail.com>

* Fix e2e test for aio_write

Signed-off-by: z1cheng <imchench@gmail.com>

* Remove redundant spaces to fix the 2e test

Signed-off-by: z1cheng <imchench@gmail.com>

---------

Signed-off-by: z1cheng <imchench@gmail.com>

docs/user-guide/nginx-configuration/configmap.md

@@ -97,6 +97,7 @@ The following table shows a configuration option's name, type, and the default v
 |[ssl-buffer-size](#ssl-buffer-size)|string|"4k"||
 |[use-proxy-protocol](#use-proxy-protocol)|bool|"false"||
 |[proxy-protocol-header-timeout](#proxy-protocol-header-timeout)|string|"5s"||
+|[enable-aio-write](#enable-aio-write)|bool|"true"||
 |[use-gzip](#use-gzip)|bool|"false"||
 |[use-geoip](#use-geoip)|bool|"true"||
 |[use-geoip2](#use-geoip2)|bool|"false"||
@@ -709,6 +710,10 @@ Enables or disables the [PROXY protocol](https://www.nginx.com/resources/admin-g
 Sets the timeout value for receiving the proxy-protocol headers. The default of 5 seconds prevents the TLS passthrough handler from waiting indefinitely on a dropped connection.
 _**default:**_ 5s
 
+## enable-aio-write
+
+Enables or disables the directive [aio_write](https://nginx.org/en/docs/http/ngx_http_core_module.html#aio_write) that writes files asynchronously. _**default:**_ true
+
 ## use-gzip
 
 Enables or disables compression of HTTP responses using the ["gzip" module](https://nginx.org/en/docs/http/ngx_http_gzip_module.html). MIME types to compress are controlled by [gzip-types](#gzip-types). _**default:**_ false

internal/ingress/controller/config/config.go

@@ -424,6 +424,10 @@ type Configuration struct {
 	// Example '60s'
 	ProxyProtocolHeaderTimeout time.Duration `json:"proxy-protocol-header-timeout,omitempty"`
 
+	// Enables or disables the directive aio_write that writes files files asynchronously
+	// https://nginx.org/en/docs/http/ngx_http_core_module.html#aio_write
+	EnableAioWrite bool `json:"enable-aio-write,omitempty"`
+
 	// Enables or disables the use of the nginx module that compresses responses using the "gzip" method
 	// http://nginx.org/en/docs/http/ngx_http_gzip_module.html
 	UseGzip bool `json:"use-gzip,omitempty"`
@@ -938,6 +942,7 @@ func NewDefault() Configuration {
 		SSLSessionTickets:                false,
 		SSLSessionTimeout:                sslSessionTimeout,
 		EnableBrotli:                     false,
+		EnableAioWrite:                   true,
 		UseGzip:                          false,
 		UseGeoIP:                         true,
 		UseGeoIP2:                        false,

rootfs/etc/nginx/template/nginx.tmpl

@@ -296,7 +296,10 @@ http {
     {{ end }}
 
     aio                 threads;
+
+    {{ if $cfg.EnableAioWrite }}
     aio_write           on;
+    {{ end }}
 
     tcp_nopush          on;
     tcp_nodelay         on;

test/e2e/settings/aio_write.go

@@ -0,0 +1,54 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package settings
+
+import (
+	"strings"
+
+	"github.com/onsi/ginkgo/v2"
+
+	"k8s.io/ingress-nginx/test/e2e/framework"
+)
+
+var _ = framework.DescribeSetting("aio-write", func() {
+	f := framework.NewDefaultFramework("aio-write")
+
+	ginkgo.It("should be enabled by default", func() {
+		f.WaitForNginxConfiguration(
+			func(cfg string) bool {
+				return strings.Contains(cfg, "aio_write on")
+			})
+	})
+
+	ginkgo.It("should be enabled when setting is true", func() {
+		f.UpdateNginxConfigMapData("enable-aio-write", "true")
+
+		f.WaitForNginxConfiguration(
+			func(cfg string) bool {
+				return strings.Contains(cfg, "aio_write on")
+			})
+	})
+
+	ginkgo.It("should be disabled when setting is false", func() {
+		f.UpdateNginxConfigMapData("enable-aio-write", "false")
+
+		f.WaitForNginxConfiguration(
+			func(cfg string) bool {
+				return !strings.Contains(cfg, "aio_write on")
+			})
+	})
+})