In one example in accordance with the present disclosure, a method for managing objects stored in memory may include identifying a first object in a heap. The heap may be accessed by a plurality of mutator threads executing within a first plurality of operating system processes. The method may also include determining that the first object is a reachable object and determining that a first range of memory locations in the heap does not contain any reachable object. The method may also include receiving an allocation request from a second mutator thread from the plurality of mutator threads and allocating a first free chunk of memory including at least a part of the first range of memory locations to the second mutator thread.