Discworld Thief Of Time A Discworld Novel #26 Terry Pratchett 2008
Time itself is threatened and it's up to the History Monks to save it.
Everybody wants more time.
Which is why, on Discworld, only the experts can manage it the venerable Monks of History who store it and pump it from where it's wasted, like underwater (how much time does a codfish really need?) to places like cities, where busy denizens lament never having enough of it.