Merge pull request #449 from ErikDubbelboer/unstable

added explanation for the magic 511 backlog number

src/anet.c

@@ -262,7 +262,11 @@ static int anetListen(char *err, int s, struct sockaddr *sa, socklen_t len) {
         close(s);
         return ANET_ERR;
     }
-    if (listen(s, 511) == -1) { /* the magic 511 constant is from nginx */
+
+    /* Use a backlog of 512 entries. We pass 511 to the listen() call because
+     * the kernel does: backlogsize = roundup_pow_of_two(backlogsize + 1);
+     * which will thus give us a backlog of 512 entries */
+    if (listen(s, 511) == -1) {
         anetSetError(err, "listen: %s", strerror(errno));
         close(s);
         return ANET_ERR;