diff --git a/ugreen.c b/ugreen.c
index 951fcbb1..f90fab0b 100644
--- a/ugreen.c
+++ b/ugreen.c
@@ -6,14 +6,13 @@
 
 TODO
 
-configurable stack size
 io and sleep management
 
 */
 
 #include "uwsgi.h"
 
-#define GREEN_STACK_SIZE 128 * 1024
+#define UGREEN_DEFAULT_STACKSIZE 128*1024
 
 extern struct uwsgi_server uwsgi;
 
@@ -137,11 +136,16 @@ void u_green_init(struct uwsgi_server *uwsgi) {
 	struct wsgi_request *wsgi_req = uwsgi->wsgi_requests ;
 
 	int i;
+	size_t u_stack_size = UGREEN_DEFAULT_STACKSIZE ;
 
 
 	PyMethodDef *uwsgi_function;
 
-	fprintf(stderr,"initializing %d uGreen threads with stack size of %lu (%lu KB)\n", uwsgi->async, (unsigned long) GREEN_STACK_SIZE,  (unsigned long) GREEN_STACK_SIZE/1024);
+	if (uwsgi->ugreen_stackpages > 0) {
+		u_stack_size = uwsgi->ugreen_stackpages * uwsgi->page_size ;
+	}
+
+	fprintf(stderr,"initializing %d uGreen threads with stack size of %lu (%lu KB)\n", uwsgi->async, (unsigned long) u_stack_size,  (unsigned long) u_stack_size/1024);
 
 
 	uwsgi->ugreen_contexts = malloc( sizeof(ucontext_t*) * uwsgi->async);
@@ -158,7 +162,7 @@ void u_green_init(struct uwsgi_server *uwsgi) {
 			exit(1);
 		}
 		getcontext(uwsgi->ugreen_contexts[i]);
-		uwsgi->ugreen_contexts[i]->uc_stack.ss_sp = mmap(NULL, GREEN_STACK_SIZE + uwsgi->page_size*2 , PROT_READ | PROT_WRITE | PROT_EXEC, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0) + uwsgi->page_size;
+		uwsgi->ugreen_contexts[i]->uc_stack.ss_sp = mmap(NULL, u_stack_size + (uwsgi->page_size*2) , PROT_READ | PROT_WRITE | PROT_EXEC, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0) + uwsgi->page_size;
 		if (!uwsgi->ugreen_contexts[i]->uc_stack.ss_sp) {
 			perror("mmap()");
 			exit(1);
@@ -168,11 +172,11 @@ void u_green_init(struct uwsgi_server *uwsgi) {
 			perror("mprotect()");
 			exit(1);
 		}
-		if (mprotect(uwsgi->ugreen_contexts[i]->uc_stack.ss_sp + GREEN_STACK_SIZE, uwsgi->page_size, PROT_NONE)) {
+		if (mprotect(uwsgi->ugreen_contexts[i]->uc_stack.ss_sp + u_stack_size, uwsgi->page_size, PROT_NONE)) {
 			perror("mprotect()");
 			exit(1);
 		}
-		uwsgi->ugreen_contexts[i]->uc_stack.ss_size = GREEN_STACK_SIZE ;
+		uwsgi->ugreen_contexts[i]->uc_stack.ss_size = u_stack_size ;
 		uwsgi->ugreen_contexts[i]->uc_link = NULL;
 		makecontext(uwsgi->ugreen_contexts[i], (void (*) (void)) &u_green_request, 3, uwsgi, wsgi_req, i);
 		wsgi_req->async_status = UWSGI_ACCEPTING;
diff --git a/uwsgi.c b/uwsgi.c
index 1cbe8782..de6135bb 100644
--- a/uwsgi.c
+++ b/uwsgi.c
@@ -357,6 +357,7 @@ int main(int argc, char *argv[], char *envp[]) {
 #endif
 #ifdef UWSGI_UGREEN
 		{"ugreen", no_argument, &uwsgi.ugreen, 1},
+		{"ugreen-stacksize", required_argument, 0, LONG_ARGS_UGREEN_PAGES},
 #endif
 		{"version", no_argument, 0, LONG_ARGS_VERSION},
 		{0, 0, 0, 0}
@@ -2277,6 +2278,11 @@ void manage_opt(int i, char *optarg) {
 	case LONG_ARGS_ASYNC:
 		uwsgi.async = atoi(optarg);
 		break;
+#ifdef UWSGI_UGREEN
+	case LONG_ARGS_UGREEN_PAGES:
+		uwsgi.ugreen_stackpages = atoi(optarg);
+		break;
+#endif
 #ifndef UNBIT
 	case LONG_ARGS_VERSION:
 		fprintf(stdout, "uWSGI %s\n", UWSGI_VERSION);
diff --git a/uwsgi.h b/uwsgi.h
index b7b4285d..29c6170c 100644
--- a/uwsgi.h
+++ b/uwsgi.h
@@ -125,6 +125,7 @@ PyAPI_FUNC(PyObject *) PyMarshal_ReadObjectFromString(char *, Py_ssize_t);
 #define LONG_ARGS_SNMP			17019
 #define LONG_ARGS_SNMP_COMMUNITY	17020
 #define LONG_ARGS_ASYNC			17021
+#define LONG_ARGS_UGREEN_PAGES		17022
 
 #define UWSGI_OK	0
 #define UWSGI_AGAIN	1
@@ -409,6 +410,7 @@ struct uwsgi_server {
 
 #ifdef UWSGI_UGREEN
 	int ugreen;
+	int ugreen_stackpages;
 	ucontext_t ugreenmain;
 	ucontext_t **ugreen_contexts;
 #endif