A method, system, and program for assigning sections within a memory heap for efficient garbage collection of large objects are provided. A first portion of a memory heap is distributed among a first number of sections from among multiple sections, wherein the first number of sections correspond to a number of helper threads allocable for bitwise sweeping of the memory heap during garbage collection. A section portion of the memory heap is distribution among a second number of sections, wherein a size of the memory heap distribution of the second number of sections progressively decreases, such that the total number of sections within the memory is minimized, but any disparity between each of the helper threads completing sweeps of all the sections is reduced.