Mainstream: Dynamic Stem-Sharing for Multi-Tenant Video Processing

Mainstream is a new video analysis system that jointly adapts concurrent applications sharing fixed edge resources to maximize aggregate result quality. Mainstream exploits partial-DNN (deep neural network) compute sharing among applications trained through transfer learning from a common base DNN model, decreasing aggregate per-frame compute time. Based on the available resources and mix of applications running on an edge node, Mainstream automatically determines at deployment time the right trade-off between using more specialized DNNs to improve per-frame accuracy, and keeping more of the unspecialized base model to increase sharing and process more frames per second. Experiments with several datasets and event detection tasks on an edge node confirm that Mainstream improves mean event detection F1-scores by up to 47% relative to a static approach of retraining only the last DNN layer and sharing all others ("Max-Sharing") and by 87X relative to the common approach of using fully independent per-application DNNs ("No-Sharing").