Execution and Timing¶
The two main functions for the postprocessing algorithms are the low treewidth graph decomposition and the low treewidth graph solve. Graph decomposition takes place on the postprocessing server during the D-Wave 2000Q QPU access time for the previous problem, while the low treewidth solve is interwoven within the QPU duty cycle.
Figure 100 shows how a set of samples are batched and sent through the postprocessing solver as the next batch is being computed by the QPU. The total time spent postprocessing samples is provided in the timing structure as total_post_processing_time. Since all but the last batch are processed during the QPU duty cycle, the additional overhead time for postprocessing, post_processing_overhead_time, corresponds to the time spent processing the final batch.

Fig. 100 D-Wave QPU timing structure¶
For more details about the timing structure, see Solver Computation Time.