For 2gpus, please try to trigger training as below spec. Per the latest result from Nvidia internal team, training with 2 gpus(V100), the AP can get 33.2 in the end.
seed: 123
use_amp: False
warmup_steps: 50000
checkpoint: “/workspace/tlt-experiments/mask_rcnn/resnet50.hdf5”
learning_rate_steps: “[360000, 540000]”
learning_rate_decay_levels: “[0.1, 0.01]”
total_steps: 720000
train_batch_size: 2
eval_batch_size: 8
num_steps_per_eval: 60000
momentum: 0.9
l2_weight_decay: 0.00002
warmup_learning_rate: 0.00001
init_learning_rate: 0.005