MallocInternals - glibc wiki

One Heap to malloc them all, One Heap to free them, One Heap to coalesce, and in the memory bind them... Overview of Malloc The GNU C library's (glibc's) malloc library contains a handful of functions that manage allocated memory in the application's address space. The glibc malloc is derived from ptmalloc (pthreads malloc), which is derived from dlmalloc (Doug Lea malloc). This malloc is a "heap"