[backport -> release/3.3.x] perf(proxy): use more reasonable keepalive default value for Nginx tuning

CHANGELOG/unreleased/kong/11515.yaml

@@ -0,0 +1,7 @@
+message: Bumped the default value of `upstream_keepalive_pool_size` to `512` and `upstream_keepalive_max_requests` to `1000`
+type: performance
+scope: Configuration
+prs:
+  - 11515
+jiras:
+  - "FTI-4868"

changelog/unreleased/kong/optimize_keepalive_parameters.yml

@@ -0,0 +1,3 @@
+message: Bumped default values of `nginx_http_keepalive_requests` and `upstream_keepalive_max_requests` to `10000`.
+type: performance
+scope: Configuration

kong.conf.default

@@ -960,26 +960,26 @@
                                   # `text/html`, `application/json`, and
                                   # `application/xml`.
 
-#upstream_keepalive_pool_size = 60  # Sets the default size of the upstream
-                                    # keepalive connection pools.
-                                    # Upstream keepalive connection pools
-                                    # are segmented by the `dst ip/dst
-                                    # port/SNI` attributes of a connection.
-                                    # A value of `0` will disable upstream
-                                    # keepalive connections by default, forcing
-                                    # each upstream request to open a new
-                                    # connection.
-
-#upstream_keepalive_max_requests = 100  # Sets the default maximum number of
-                                        # requests than can be proxied upstream
-                                        # through one keepalive connection.
-                                        # After the maximum number of requests
-                                        # is reached, the connection will be
-                                        # closed.
-                                        # A value of `0` will disable this
-                                        # behavior, and a keepalive connection
-                                        # can be used to proxy an indefinite
-                                        # number of requests.
+#upstream_keepalive_pool_size = 512  # Sets the default size of the upstream
+                                     # keepalive connection pools.
+                                     # Upstream keepalive connection pools
+                                     # are segmented by the `dst ip/dst
+                                     # port/SNI` attributes of a connection.
+                                     # A value of `0` will disable upstream
+                                     # keepalive connections by default, forcing
+                                     # each upstream request to open a new
+                                     # connection.
+
+#upstream_keepalive_max_requests = 1000  # Sets the default maximum number of
+                                         # requests than can be proxied upstream
+                                         # through one keepalive connection.
+                                         # After the maximum number of requests
+                                         # is reached, the connection will be
+                                         # closed.
+                                         # A value of `0` will disable this
+                                         # behavior, and a keepalive connection
+                                         # can be used to proxy an indefinite
+                                         # number of requests.
 
 #upstream_keepalive_idle_timeout = 60   # Sets the default timeout (in seconds)
                                         # for which an upstream keepalive
@@ -1137,6 +1137,16 @@
                                                 # It is recommended to set it to at least (number of regex paths * 2)
                                                 # to avoid high CPU usages.
 
+#nginx_http_keepalive_requests = 10000 # Sets the maximum number of client requests that can be served through one
+                                       # keep-alive connection. After the maximum number of requests are made,
+                                       # the connection is closed.
+                                       # Closing connections periodically is necessary to free per-connection
+                                       # memory allocations. Therefore, using too high maximum number of requests
+                                       # could result in excessive memory usage and not recommended.
+                                       # See: https://nginx.org/en/docs/http/ngx_http_core_module.html#keepalive_requests
+
+
+
 #------------------------------------------------------------------------------
 # DATASTORE
 #------------------------------------------------------------------------------

kong/templates/kong_defaults.lua

@@ -62,8 +62,8 @@ status_ssl_cert_key = NONE
 headers = server_tokens, latency_tokens
 trusted_ips = NONE
 error_default_type = text/plain
-upstream_keepalive_pool_size = 60
-upstream_keepalive_max_requests = 100
+upstream_keepalive_pool_size = 512
+upstream_keepalive_max_requests = 10000
 upstream_keepalive_idle_timeout = 60
 allow_debug_header = off
 
@@ -84,6 +84,9 @@ nginx_http_ssl_prefer_server_ciphers = NONE
 nginx_http_ssl_dhparam = NONE
 nginx_http_ssl_session_tickets = NONE
 nginx_http_ssl_session_timeout = NONE
+nginx_http_lua_regex_match_limit = 100000
+nginx_http_lua_regex_cache_max_entries = 8192
+nginx_http_keepalive_requests = 10000
 nginx_stream_ssl_protocols = NONE
 nginx_stream_ssl_prefer_server_ciphers = NONE
 nginx_stream_ssl_dhparam = NONE
@@ -93,8 +96,6 @@ nginx_proxy_real_ip_header = X-Real-IP
 nginx_proxy_real_ip_recursive = off
 nginx_admin_client_max_body_size = 10m
 nginx_admin_client_body_buffer_size = 10m
-nginx_http_lua_regex_match_limit = 100000
-nginx_http_lua_regex_cache_max_entries = 8192
 
 client_body_buffer_size = 8k
 real_ip_header = X-Real-IP

spec/01-unit/04-prefix_handler_spec.lua

@@ -1116,7 +1116,7 @@ describe("NGINX conf compiler", function()
                            nil, true)
             assert.matches("daemon on;", contents, nil, true)
             assert.matches("listen 0.0.0.0:9000;", contents, nil, true)
-            assert.not_matches("keepalive", contents, nil, true)
+            assert.not_matches("keepalive%s+%d+", contents)
           end)
         end)
       end)