Running code in loop inside gazebo-ros plugin

edit

Any time I have used gazebo-ros plugin of any type, I would always define an update function that is called on every world update and but the code I need to run there.

this->updateConnection = event::Events::ConnectWorldUpdateBegin(
                                boost::bind(&MyPlugin::onUpdate, this));

But now I need the code to be run even if the simulation is paused. What can I use to achieve this?