--- a/src/http/modules/ngx_http_upstream_keepalive_module.c
+++ b/src/http/modules/ngx_http_upstream_keepalive_module.c
@@ -12,7 +12,6 @@
 
 typedef struct {
     ngx_uint_t                         max_cached;
-    ngx_uint_t                         single;       /* unsigned:1 */
 
     ngx_queue_t                        cache;
     ngx_queue_t                        free;
@@ -223,36 +222,11 @@ ngx_http_upstream_get_keepalive_peer(ngx
 
     kp->failed = 0;
 
-    /* single pool of cached connections */
-
-    if (kp->conf->single && !ngx_queue_empty(&kp->conf->cache)) {
-
-        q = ngx_queue_head(&kp->conf->cache);
-
-        item = ngx_queue_data(q, ngx_http_upstream_keepalive_cache_t, queue);
-        c = item->connection;
-
-        ngx_queue_remove(q);
-        ngx_queue_insert_head(&kp->conf->free, q);
-
-        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0,
-                       "get keepalive peer: using connection %p", c);
-
-        c->idle = 0;
-        c->log = pc->log;
-        c->read->log = pc->log;
-        c->write->log = pc->log;
-        c->pool->log = pc->log;
-
-        pc->connection = c;
-        pc->cached = 1;
-
-        return NGX_DONE;
-    }
+    /* ask balancer */
 
     rc = kp->original_get_peer(pc, kp->data);
 
-    if (kp->conf->single || rc != NGX_OK) {
+    if (rc != NGX_OK) {
         return rc;
     }
 
@@ -552,7 +526,8 @@ ngx_http_upstream_keepalive(ngx_conf_t *
     for (i = 2; i < cf->args->nelts; i++) {
 
         if (ngx_strcmp(value[i].data, "single") == 0) {
-            kcf->single = 1;
+            ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
+                               "the \"single\" parameter is deprecated");
             continue;
         }