Taking back control of HPC file systems with Robinhood Policy Engine

Abstract: Today, the largest Lustre file systems store billions of entries. On such systems, classic tools based on namespace scanning become unusable. Operations such as managing file lifetime, scheduling data copies, and generating overall filesystem statistics become painful as they require collecting, sorting and aggregating information for billions of records. Robinhood Policy Engine is an open source software developed to address these challenges. It makes it possible to schedule automatic actions on huge numbers of filesystem entries. It also gives a synthetic understanding of file systems contents by providing overall statistics about data ownership, age and size profiles. Even if it can be used with any POSIX filesystem, Robinhood supports Lustre specific features like OSTs, pools, HSM, ChangeLogs, and DNE. It implements specific support for these features, and takes advantage of them to manage Lustre file systems efficiently.