Dear XFS Experts, as you may or may not know, XFS on NVMe was used as part of the #1 entry to the IO500 benchmarks, as announced at ISC21. That entry swept away the other competition (albeit on large custom hardware), including systems using Intel’s DAOS using Octane/PMem, WekaIO, Lustre, GekkoFS and others. There’s no publication associated with it, however there’s a video presenting how they did it: https://www.youtube.com/watch?v=BJpkpA6hsDc In it they describe how they used XFS for storing data chunks, and RocksDB for storing metadata. I’m trying to dig deeper on how they could have used XFS, and in particular how they could have used RDMA to access XFS data. The XFS DAX mode as far as I’m aware requires PMem rather than NVMe? Do you have any ideas how they could have been able to utilise RDMA so that node A can directly access data chunks stored on XFS on node B? Is the only approach to mmap the chunk on node B and then RDMA it to/from node A? Kind regards, Dan
