+/********** Tracing **********/
+/* from surf_instr.c */
+void TRACE_surf_host_set_power(double date, const char *resource, double power);
+void TRACE_surf_link_set_bandwidth(double date, const char *resource, double bandwidth);
+void TRACE_surf_link_set_latency(double date, const char *resource, double latency);
+
+