Hinting for Goodness' Sake

Operating systems typically don't know how resource allocation affects applications. Applications are often blind to varying resource levels. The solution to both these problems is to share information between applications and the system in the form of hints. Traditionally, hinting has been added to systems as an afterthought; we make hints first-class entities and introduce a system structure designed from the outset to support them. We advocate goodness hints as the general mechanism for informed resource allocation and application adaptation.