Baoverlay

Abstract

Container storage commonly relies on overlay file systems to interpose read-only container images upon backing file systems. While being transparent to and compatible with most existing backing file systems, the overlay file-system approach imposes nontrivial I/O overhead to containerized applications, especially for writes: To write a file originating from a read-only container image, the whole file will be copied to a separate, writable storage layer, resulting in long write latency and inefficient use of container storage. In this paper, we present BAOverlay, a lightweight, block-accessible overlay file system: Equipped with a new block-accessibility attribute, BAOverlay not only exploits the benefit of using an asynchronous copy-on-write mechanism for fast file updates but also enables a new file format for efficient use of container storage space. We have developed a prototype of BAOverlay upon Linux Ext4. Our evaluation with both micro-benchmarks and real-world applications demonstrates the effectiveness of BAOverlay with improved write performance and on-demand container storage usage. CCS CONCEPTS • Information systems → Storage virtualization; • Software and its engineering → File systems management.

Troy: Efficient Service Deployment for Windows Systems

“…It brings the virtualization overhead in runtime, lowering the user experience. More importantly, they can hardly support virtualizing a specific hardware, such as graphic processing unit (GPU), due to the limitation of nested virtual machine (VM) [7]. Although VOI brings native performance, the loading of a large image, typically over 30 GB, leads to unacceptable loading latency limited by the network bandwidth.…”