Callbacks are not being called, gradient norm not getting logged,how to debug these scenarios? 
❓ Questions and Help

I have defined a callback for the on_epoch_end event. Also, I have defined track_grad_norm = 1, which I think is also kind of a callback.
When I used --fast_dev_run or --limit_train_batches and --limit_val_batches the callback(including gradient norm plot) got executed properly.
When I run without the above flags, on_epoch_end is sometimes not executing (or silently failing?), gradient norms are not getting plotted at all.
Checkpoint saving callback is always successfully executing.

Now I am unsure how do I debug this scenario. There is no error messages logged.
What's your environment?

OS: Linux
Packaging:- pip
Version:- 0.9.0rc15