Using the dragonfly network model, the packet generation is off in the optimistic mode as compared to sequential mode. This problem can be reproduced using the synthetic workload program for the dragonfly model. There are some debug statements to display the number of packets being generated and finished (they are different every time in optimistic mode and the number does not agree with sequential mode). The dragonfly model has no packets left in any of its terminal or router queues so it seems to be routing packets correctly. However, it issues model-net idle event calls to the model-net scheduler that could be causing the problem?

Here is how to reproduce the problem:

mpirun -np 4 ./src/models/network-workloads/model-net-synthetic --sync=3 --num_messages=20 --traffic=2 --arrival_time=100.0 -- ../src/models/network-workloads/conf/modelnet-synthetic-dragonfly.conf

This issue is blocking me with my trace runs at a large-scale so I am marking this as a blocker.