[c-nsp] Fabric buffer-reserve high: what does it actually do?

[John Neiberger]

An app owner (Oracle database) has recommended that we enable "fabric
buffer-reserve high" to solve some Oracle problem they seem to be
running into. We haven't had a chance to investigate their problem
yet, so we're not going to change that just because they asked us to.
However, I'm curious about what it actually does and how it interacts
with the hardware buffers on the 67xx line cards. I did a quick Google
search, but didn't find a lot of detail.

Thanks,
John