  Training a state-of-the-art deep neural network (DNN) is a
computationally-expensive and time-consuming process, which incentivizes deep
learning developers to debug their DNNs for computational performance. However,
effectively performing this debugging requires intimate knowledge about the
underlying software and hardware systems---something that the typical deep
learning developer may not have. To help bridge this gap, we present Skyline: a
new interactive tool for DNN training that supports in-editor computational
performance profiling, visualization, and debugging. Skyline's key contribution
is that it leverages special computational properties of DNN training to
provide (i) interactive performance predictions and visualizations, and (ii)
directly manipulatable visualizations that, when dragged, mutate the batch size
in the code. As an in-editor tool, Skyline allows users to leverage these
diagnostic features to debug the performance of their DNNs during development.
An exploratory qualitative user study of Skyline produced promising results;
all the participants found Skyline to be useful and easy to use.
