Awesome

mergerfs-io-passthrough

A library for direct mergerfs file access.

Experimental - use at your own risk.

When injected into a process (using LD_PRELOAD), it intercepts calls to open(2) and redirects them to the underlying filesystem.

For example, if you want to open /mnt/pool/foo.txt, it will open /mnt/disk1/foo.txt instead. The path mapping is obtained using the IOCTL_FILE_INFO request provided by mergerfs.

In practice, this means you can mount your pool with cache.files=off (better performance) and still use mmap. This is particularly useful for rtorrent which may otherwise be unstable when accessing mergerfs files (I experienced random crashes during hash checking).

A wrapper script rtorrent-mfs for launching rtorrent is included.

Install

make
sudo make install