/** Called when the machine is turned on or off (called AFTER the change) */
static xbt::signal<void(Host const&)> on_state_change;
/** Called when the speed of the machine is changed (called AFTER the change)
* (either because of a pstate switch or because of an external load event coming from the profile) */
static xbt::signal<void(Host const&)> on_speed_change;
/** Called when the machine is turned on or off (called AFTER the change) */
static xbt::signal<void(Host const&)> on_state_change;
/** Called when the speed of the machine is changed (called AFTER the change)
* (either because of a pstate switch or because of an external load event coming from the profile) */
static xbt::signal<void(Host const&)> on_speed_change;