robinhood

There's a tool called Robinhood which started its life around 2004 [0], In turn, Robinhood Markets are founded in 2013. Imagine knowing that Robinhood exists as one of the most popular (or the only) policy engines for large (EB sized) filesystems for but still naming your new company Robinhood. I think Robinhood Markets should C&D immediately and find themselves a new name. [0]: https://github.com/cea-hpc/robinhood

Assuming this was a "scratch" HPC filesystem, as I'd guess, "scratch" is used advisedly -- users should be prepared to lose anything on it, not that it should happen with finger trouble. However, if I understand correctly from the comments, I'm surprised at the tools, and that the vendor was managing the filesystem. I'd expect to use https://github.com/cea-hpc/robinhood/wiki with Lustre, though I thought I'd seen a Cray presentation about tools of their own.

HPC sites are likely to use https://github.com/cea-hpc/robinhood/wiki/Documentation. While its user interface isn't SQL, it does store the filesystem metadata in an SQL database (updated from changesets for Lustre filesystems). You don't want to run -- or, specifically, have users run -- ls, find, or du on significant amounts of a typical large filesystem. (As I understand it, you could do something similar to lustre with Isilon/OneFS, for instance.) The metadata store of OrangeFS (PVFS2) is implemented with a database, though a key-value one, and one of the project ideas for it is to search that directly.