BUSE

I wonder if this could replace most uses of NBD (network block devices), and/or help get iSCSI into userspace where more flexible load-balancing policy can be implemented. It also reminds me of attempts to define BUSE[0][1][2], which would have been a block device equivalent of FUSE. IIRC attempts to get BUSE into the Linux kernel have been blocked for performance reasons -- the FUSE protocol isn't well designed and is only barely acceptable for VFS. If io_uring (+ careful use of zero-copy) has fixed the performance issues with userspace block devices, maybe it would be applicable to FUSE (or FUSE-v2)? I've tried using io_uring with the current FUSE protocol to reduce syscall overhead and it kinda works, but a protocol designed to operate in that mode from the beginning would be even better. [0] https://github.com/acozzette/BUSE [1] https

> BTW does anyone know if there is something similar to FUSE, but for block-devices? https://github.com/acozzette/BUSE The disclaimer says it's experimental, though.