Correct, Fast Remote Persistence

Abstract: Persistence of updates to remote byte-addressable persistent memory (PM), using RDMA operations (RDMA updates), is a poorly understood subject. Visibility of RDMA updates on the remote server is not the same as persistence of those updates. The remote server's configuration has significant implications on what it means for RDMA updates to be persistent on the remote server. This leads to significant implications on methods needed to correctly persist those updates. This paper presents a comprehensive taxonomy of system configurations and the corresponding methods to ensure correct remote persistence of RDMA updates. We show that the methods for correct, fast remote persistence vary dramatically, with corresponding performance trade offs, between different remote server configurations.