D4C: Leveraging Delta Encodings for Faster and Lighter Container Image Updating

Container images sometimes take tens to hundreds of megabytes in size and require many network resources to be transferred. Especially in low-bandwidth network environments like edge computing, frequent image updating will be difficult and increase the network cost. In this talk, I will present "D4C", a software that provides faster and lighter image updating with delta encodings. Delta encodings reduce data size, but generating and applying deltas is a time-consuming operation. D4C utilizes some techniques to reduce them including merge-based delta management and applying deltas lazily. D4C reduces the data size to update images by up to 95% and provides about 10x faster updating in low-bandwidth networks than the state-of-the-art approach. Benchmarks with PostgreSQL and PyTorch showed that their performance degradation caused by D4C is negligible.