How can I check if my filesystem supports reflinks?

[amoosebitmymom]

Hi
I am using a relatively obscure filesystem in my project. The documentation contains no reference to reflinks. However I want to be absolutely sure. Is there an operation I could simulate using DVC to determine whether or not my filesystem supports reflinks?
Thanks

[skshetry]

dvc doctor has a Cache types section in the output. If you are not seeing it in the output or has an error link, either you are invoking from a non-dvc repository or have a missing cache directory).
(In that case, I'd dvc init && mkdir -p .dvc/cache/files/md5).

[amoosebitmymom]

Thanks, that determined it. Is there benefit of using hardlinks over symlinks? Or does it not matter if reflinks aren't available

[skshetry]

Practically speaking, I don't think there is much benefit of using hardlink compared to symlink. Hardlink is a bit faster and efficient, but there are limits to how many hardlink you can create in some filesystems. And the performance gap is very small between both of those link types.

You can read some comparisons in File link types for the DVC cache.

Also see #2459.