diff --git a/plugins/python/uwsgi_pymodule.c b/plugins/python/uwsgi_pymodule.c
index b4f99726..b23ff8d7 100644
--- a/plugins/python/uwsgi_pymodule.c
+++ b/plugins/python/uwsgi_pymodule.c
@@ -2460,7 +2460,9 @@ PyObject *py_uwsgi_cache_get(PyObject * self, PyObject * args) {
 	char buffer[0xffff];
 	PyObject *res;
 
+#ifdef UWSGI_DEBUG
 	struct timeval tv, tv2;
+#endif
 
 	if (!PyArg_ParseTuple(args, "s#|s:cache_get", &key, &keylen, &remote)) {
 		return NULL;
@@ -2473,14 +2475,18 @@ PyObject *py_uwsgi_cache_get(PyObject * self, PyObject * args) {
 		}
 	}
 	else if (uwsgi.cache_max_items) {
+#ifdef UWSGI_DEBUG
 		gettimeofday(&tv, NULL); 
+#endif
 		uwsgi_lock(uwsgi.cache_lock);
 		value = uwsgi_cache_get(key, keylen, &valsize);
 		res = PyString_FromStringAndSize(value, valsize);
+#ifdef UWSGI_DEBUG
 		gettimeofday(&tv2, NULL); 
 		if ((tv2.tv_sec* (1000*1000) + tv2.tv_usec) - (tv.tv_sec* (1000*1000) + tv.tv_usec) > 30000) {
 			uwsgi_log("[slow] cache get done in %d microseconds (%llu bytes value)\n", (tv2.tv_sec* (1000*1000) + tv2.tv_usec) - (tv.tv_sec* (1000*1000) + tv.tv_usec), (unsigned long long) valsize);
 		}
+#endif
 		uwsgi_unlock(uwsgi.cache_lock);
 		return res;
 	}
diff --git a/protocol.c b/protocol.c
index 492c5b38..d1c62536 100644
--- a/protocol.c
+++ b/protocol.c
@@ -82,7 +82,7 @@ int uwsgi_enqueue_message(char *host, int port, uint8_t modifier1, uint8_t modif
 	if (!timeout)
 		timeout = 1;
 
-	if (size > 0xFFFF) {
+	if (size > 0xffff) {
 		uwsgi_log( "invalid object (marshalled) size\n");
 		return -1;
 	}
diff --git a/uwsgi.c b/uwsgi.c
index 9724f2b8..55f599d8 100644
--- a/uwsgi.c
+++ b/uwsgi.c
@@ -1063,15 +1063,20 @@ int uwsgi_start(void *v_argv) {
 
 	if (uwsgi.cache_max_items > 0) {
 
-		if (!uwsgi.cache_blocksize) uwsgi.cache_blocksize = 0xffff;
+		if (!uwsgi.cache_blocksize) uwsgi.cache_blocksize = UMAX16;
 
-		uwsgi.cache_hashtable = (uint64_t *) mmap(NULL, sizeof(uint64_t) * 0xffff, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANON, -1, 0);
+		if (uwsgi.cache_blocksize % uwsgi.page_size != 0) {
+			uwsgi_log("invalid cache blocksize %llu: must be a multiple of memory page size (%d bytes)\n", (unsigned long long) uwsgi.cache_blocksize, uwsgi.page_size);
+			exit(1);
+		}
+
+		uwsgi.cache_hashtable = (uint64_t *) mmap(NULL, sizeof(uint64_t) * UMAX16, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANON, -1, 0);
 		if (!uwsgi.cache_hashtable) {
 			uwsgi_error("mmap()");
                         exit(1);
 		}
 
-		memset(uwsgi.cache_hashtable, 0, sizeof(uint64_t) * 0xffff);
+		memset(uwsgi.cache_hashtable, 0, sizeof(uint64_t) * UMAX16);
 
 		uwsgi.cache_unused_stack = (uint64_t *) mmap(NULL, sizeof(uint64_t) * uwsgi.cache_max_items, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANON, -1, 0);
                 if (!uwsgi.cache_unused_stack) {
@@ -1105,6 +1110,8 @@ int uwsgi_start(void *v_argv) {
         	uwsgi_lock_init(uwsgi.cache_lock);
 
 		uwsgi.p[111] = &uwsgi_cache_plugin;
+
+		uwsgi_log("*** Cache subsystem initialized: %dMB preallocated ***\n", ((sizeof(uint64_t) * UMAX16) + (sizeof(uint64_t) * uwsgi.cache_max_items) + (uwsgi.cache_blocksize * uwsgi.cache_max_items) + (sizeof(struct uwsgi_cache_item) * uwsgi.cache_max_items)) / (1024*1024));
 	}
 
 	/* plugin initialization */
diff --git a/uwsgi.h b/uwsgi.h
index 7aceaef1..cdcb3a1a 100644
--- a/uwsgi.h
+++ b/uwsgi.h
@@ -4,6 +4,8 @@
 
 #define UWSGI_VERSION	"0.9.7-dev"
 
+#define UMAX16	65536
+
 #define uwsgi_error(x)  uwsgi_log("%s: %s [%s line %d]\n", x, strerror(errno), __FILE__, __LINE__);
 #define uwsgi_debug(x, ...) uwsgi_log("[uWSGI DEBUG] " x, __VA_ARGS__);
 #define uwsgi_rawlog(x) if (write(2, x, strlen(x)) != strlen(x)) uwsgi_error("write()")