Tweak buffer and add some poor mans statistics

sf-buffer/src/sf_replay.cpp

@@ -42,7 +42,7 @@ int main (int argc, char *argv[]) {
     auto ctx = zmq_ctx_new();
 
     auto socket = zmq_socket(ctx, ZMQ_PUSH);
-    int sndhwm = 1;
+    int sndhwm = 10;
     if (zmq_setsockopt(socket, ZMQ_SNDHWM, &sndhwm, sizeof(sndhwm)) != 0) {
         throw runtime_error(strerror (errno));
     };