Depending on what exactly you mean by "hand it a block of memory to manage", you can do this with jemalloc's extent hook functionality. Though that's meant for

Depending on what exactly you mean by "hand it a block of memory to manage", you can do this with jemalloc's extent hook functionality. Though that's meant for "I have some long-lived data structures, I want all their memory stored on hugepages" more than "I have this small-ish data structure, I want to batch its allocations together".