Improving the Performance of Asynchronous Replication with Mixed-Mode Copying

IBM Scale Out Network Attached Storage (SONAS) supports asynchronous replication to copy files to a remote site for disaster recovery. In SONAS R1.3.1, We developed mixed-mode copying by combining size-based copying with directory-based copying to improve the performance of asynchronous replication for typical real-world file tree structures where large files reside in the same directory. This combined method balances the workload of copying large files and prevents the performance degradation due to concurrent copying of small files in a single directory. We verified our mixed-mode copying increased the performance of asynchronous replication by up to 148% compared to either approach by itself on both virtual and physical test environments.