AvaTar: Zero-Copy Archiving with New Kernel-Level Operations

The problem associated with current file archiving systems is a slow processing time owing to unnecessary data copying. To address this problem, a novel archiving system with zero-copy merging and splitting operations, referred to as AvaTar, is presented herein. For the operations, instead of copying the data, the block allocation information of the files is manipulated at the kernel level. We implemented kernel-level archiving primitives in a Linux kernel, called AvaTar-FS, and a user-level archiving tool, called AvaTar agent. Our evaluation results indicated that AvaTar required only 0.48 s to extract 1,024 files from a 4 GB archive file, which is 132-times faster when compared with traditional GNU Tar archiving. AvaTar affords practical benefits in uploading files to a real-world cloud storage system, and successfully completes the transfer of 1,024 files to Amazon Web Service cloud storage within 60.55% of the processing time required through a traditional approach.