[ori_b]

Pretty much, it's not going to matter: http://www.csl.sri.com/users/gehani/papers/SAC-2010.FUSE.pdf.

Putting ext3 into userspace led to slightly less than 10% performance degradation on postmark. Fuse really isn't an issue in most cases, and I can't imagine that this makes a huge difference on most workloads.

[olavgg]

There may be other reasons that we are not aware of, anyway learning how to build your own vfs most likely have huge advantages in the long run.