Design of CEFT-PVFS

CEFT-PVFS is a RAID-10 style parallel file system that mirrors the striped data between two groups of server nodes, one primary group and one backup group, as shown in Figure 1. There is one metadata server in each group. To make the synchronization simple, clients' requests go to the primary metadata server first. If the primary metadata server fails, all metadata requests will be redirected to the backup one. All following requests will directly go to the backup metadata server until the primary one is recovered and rejoins the system. For write requests, the data will first be written to the primary group and then be duplicated to the backup group. Four duplication (or mirroring) protocols are designed and will be discussed in Section IV.

Figure 1: Basic diagram of CEFT-PVFS.