Heating a reaction chamber or other apparatus in the absence of product wafers to a \u201ccuring\u201d temperature above a deposition temperature between the deposition of a film on a first set of semiconductor product wafers and the deposition of a film on a second set of semiconductor product wafers. Efficient startup of a graph-based computation involves precomputing data representing a runtime structure of a computation graph such that an instance of the computation graph is formed using the precomputed data for the required type of graph to form the runtime data structure for the instance of the computation graph. When the notification process is inoperable, client computers poll one or more monitoring-and-management server computer for commands. A signal VC releasing unit releases signal VCs in accordance with the decrease in the number of calls detected by the number of calls detecting unit. A second insulation layer and a second metal layer are laminated onto the lower surface.