--- fcgid_bridge.c.1725557	2016-01-19 17:13:02.316683000 +0100
+++ fcgid_bridge.c	2017-09-07 11:54:52.474053000 +0200
@@ -30,8 +30,30 @@
 #include "fcgid_spawn_ctl.h"
 #include "fcgid_protocol.h"
 #include "fcgid_bucket.h"
-#define FCGID_APPLY_TRY_COUNT 2
-#define FCGID_REQUEST_COUNT 32
+/* FCGID_REQUEST_COUNT: 
+ * how many times to attempt a spawn request */
+#define FCGID_REQUEST_COUNT 8
+/* FCGID_REQUEST_INITIAL_STEP: 
+ * The initial iterations of the inner loop */
+#define FCGID_REQUEST_INITIAL_STEP 2
+/* FCGID_REQUEST_INITIAL_SLEEP: 
+ * The initial sleep time in ms of the inner loop */
+#define FCGID_REQUEST_INITIAL_SLEEP 50
+/* FCGID_REQUEST_STEPSIZE: 
+ * every FCGID_REQUEST_COUNT loop, increase the inner loop by this size */
+#define FCGID_REQUEST_STEPSIZE 6
+/* FCGID_REQUEST_SLEEPSIZE: 
+ * every FCGID_REQUEST_COUNT loop, increase the inner loop sleeptime
+ * by FCGID_REQUEST_SLEEPSIZE miliseconds */
+#define FCGID_REQUEST_SLEEPSIZE 150
+/* FCGID_REQUEST_STEPCOUNT: 
+ * how many FCGID_REQUEST_COUNT loop iterations to increase the 
+ * inner loop by FCGID_REQUEST_STEPSIZE */
+#define FCGID_REQUEST_STEPCOUNT 4
+/* FCGID_REQUEST_SLEEPCOUNT: 
+ * how many FCGID_REQUEST_COUNT loop iterations to increase the 
+ * inner loop by FCGID_REQUEST_SLEEPSIZE msec */
+#define FCGID_REQUEST_SLEEPCOUNT 4
 #define FCGID_BRIGADE_CLEAN_STEP 32
 
 static fcgid_procnode *apply_free_procnode(request_rec *r,
@@ -425,7 +447,7 @@
 {
     fcgid_command fcgi_request;
     fcgid_bucket_ctx *bucket_ctx;
-    int i, j, cond_status;
+    int i, j, cond_status, wait_msec, try_spawn;
     const char *location = NULL;
 
     bucket_ctx = apr_pcalloc(r->pool, sizeof(*bucket_ctx));
@@ -434,34 +456,40 @@
     apr_pool_cleanup_register(r->pool, bucket_ctx,
                               bucket_ctx_cleanup, apr_pool_cleanup_null);
     procmgr_init_spawn_cmd(&fcgi_request, r, cmd_conf);
-
+    bucket_ctx->ipc.connect_timeout =
+        fcgi_request.cmdopts.ipc_connect_timeout;
+    bucket_ctx->ipc.communation_timeout =
+        fcgi_request.cmdopts.ipc_comm_timeout;
+
+    /* our initial wait time is short */
+    wait_msec = FCGID_REQUEST_INITIAL_SLEEP;
+    /* initially we try to spawn a processes after failing to apply 2 times */
+    try_spawn = FCGID_REQUEST_INITIAL_STEP;
     /* Try to get a connected ipc handle */
     for (i = 0; i < FCGID_REQUEST_COUNT; i++) {
         /* Apply a free process slot, send a spawn request if I can't get one */
-        for (j = 0; j < FCGID_APPLY_TRY_COUNT; j++) {
-            bucket_ctx->ipc.connect_timeout =
-                fcgi_request.cmdopts.ipc_connect_timeout;
-            bucket_ctx->ipc.communation_timeout =
-                fcgi_request.cmdopts.ipc_comm_timeout;
+        for (j = 0; j < try_spawn; j++) {
 
             /* Apply a process slot */
             bucket_ctx->procnode = apply_free_procnode(r, &fcgi_request);
             if (bucket_ctx->procnode)
                 break;
 
-            /* Avoid sleeping the very first time through if there are no
-               busy processes; the problem is just that we haven't spawned
-               anything yet, so waiting is pointless */
-            if (i > 0 || j > 0 || count_busy_processes(r, &fcgi_request)) {
-                apr_sleep(apr_time_from_sec(1));
+            /* We couldn't get a free process slot, if it was the very 
+               first try, lets check if any were spawned at all */
+            if (i == 0 && j == 0 
+                && count_busy_processes(r, &fcgi_request)==0) {
+                /* there are no processes so try to spawn one */
+                procmgr_send_spawn_cmd(&fcgi_request, r);
 
                 bucket_ctx->procnode = apply_free_procnode(r, &fcgi_request);
                 if (bucket_ctx->procnode)
                     break;
             }
 
-            /* Send a spawn request if I can't get a process slot */
-            procmgr_send_spawn_cmd(&fcgi_request, r);
+            /* now wait a bit for a process to free up */
+            apr_sleep(apr_time_from_msec(wait_msec));
+
         }
 
         /* Connect to the fastcgi server */
@@ -476,6 +504,40 @@
             else
                 break;
         }
+        
+        /* It seems to be busy, every iteration we try to spawn less
+         * often as its more and more likely we hit the max processes
+         * limit. Also sleep longer so we don't waste too much cycles.
+         * When nearing the end of our retry lifitime, decrease sleep
+         * time again so we still have a chance at getting a process. */
+        /* loop iterations:
+           0) 2  x  50ms =   100ms
+           1) 8  x 200ms =  1600ms
+           2) 14 x 350ms =  4900ms
+           3) 20 x 500ms = 10000ms
+           4) 26 x 650ms = 16900ms
+           5) 26 x 500ms = 13000ms
+           6) 26 x 350ms =  9100ms
+           7) 26 x 200ms =  5200ms
+                          -------- +
+                           60800ms (8x spawn, 148 apply)
+           Old: 64000ms (64x spawn, 128 apply)
+           */
+        if(i < FCGID_REQUEST_STEPCOUNT){
+            try_spawn+=FCGID_REQUEST_STEPSIZE;
+        }
+        if(i < FCGID_REQUEST_SLEEPCOUNT){
+            wait_msec+=FCGID_REQUEST_SLEEPSIZE;
+        }else{
+            /* our request count exceeds the FCGID_REQUEST_SLEEPCOUNT
+             * value, so lets give it more priority by lowering the wait
+             * and hopefulle preventing a HTTP_SERVICE_UNAVAILABLE */
+            wait_msec-=FCGID_REQUEST_SLEEPSIZE;
+        }
+        
+        /* we tried try_spawn times to get a process slot but we
+         * failed. So now try to spawn a new one. */
+        procmgr_send_spawn_cmd(&fcgi_request, r);
     }
 
     /* Now I get a connected ipc handle */