commit ca260f067b8def7f3294429c267416819e369dcb
author Maxim Dounin <mdounin@mdounin.ru> Thu Oct 05 17:43:05 2017 +0300
committer Maxim Dounin <mdounin@mdounin.ru> Thu Oct 05 17:43:05 2017 +0300
tree 7f43476c306c54883787d1e8994e85797ce2b51d
parent b034fddd12072b9471e44fae91a620f8d51258f3

Upstream hash: reordered peer checks.

This slightly reduces cost of selecting a peer if all or almost all peers
failed, see ticket #1030.  There should be no measureable difference with
other workloads.

src/http/modules/ngx_http_upstream_hash_module.c

diff --git a/src/http/modules/ngx_http_upstream_hash_module.c b/src/http/modules/ngx_http_upstream_hash_module.c
index 78e672c..d67f34d 100644
--- a/src/http/modules/ngx_http_upstream_hash_module.c
+++ b/src/http/modules/ngx_http_upstream_hash_module.c
@@ -543,13 +543,6 @@
                 continue;
             }
 
-            if (peer->server.len != server->len
-                || ngx_strncmp(peer->server.data, server->data, server->len)
-                   != 0)
-            {
-                continue;
-            }
-
             if (peer->max_fails
                 && peer->fails >= peer->max_fails
                 && now - peer->checked <= peer->fail_timeout)
@@ -561,6 +554,13 @@
                 continue;
             }
 
+            if (peer->server.len != server->len
+                || ngx_strncmp(peer->server.data, server->data, server->len)
+                   != 0)
+            {
+                continue;
+            }
+
             peer->current_weight += peer->effective_weight;
             total += peer->effective_weight;
 

src/stream/ngx_stream_upstream_hash_module.c

diff --git a/src/stream/ngx_stream_upstream_hash_module.c b/src/stream/ngx_stream_upstream_hash_module.c
index 4135379..79ad742 100644
--- a/src/stream/ngx_stream_upstream_hash_module.c
+++ b/src/stream/ngx_stream_upstream_hash_module.c
@@ -544,13 +544,6 @@
                 continue;
             }
 
-            if (peer->server.len != server->len
-                || ngx_strncmp(peer->server.data, server->data, server->len)
-                   != 0)
-            {
-                continue;
-            }
-
             if (peer->max_fails
                 && peer->fails >= peer->max_fails
                 && now - peer->checked <= peer->fail_timeout)
@@ -562,6 +555,13 @@
                 continue;
             }
 
+            if (peer->server.len != server->len
+                || ngx_strncmp(peer->server.data, server->data, server->len)
+                   != 0)
+            {
+                continue;
+            }
+
             peer->current_weight += peer->effective_weight;
             total += peer->effective_weight;