Hi linux file system experts, I want to share ext4 on the storage server to multiple initiators(node A,B) using NVMeoF. Node A will write file to ext4 on the storage server, and I will mount read-only option on Node B. Actually, the reason I do this is for a prototype test. I can't see the file's dentry and inode written in Node A on Node B unless remount(umount and then mount) it. Why is that? I think if there is file system cache(dentry, inode) on Node B, then disk IO will occur to read the data written by Node A. Curiously, drop cache on Node B and do blockdev --flushbufs, then I can access the file written by Node A. I checked the kernel code and found that flushbufs incurs sync_filesystem() which flushes the superblock and all dirty file system caches. Should the superblock data structure be flushed (updated) when accessing the disk inode? I wonder why this happens. Regards,
