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The allocator always > > > > owns it and we are just replacing the memory with a different mmap. > > > > > > Hmm, if allocator always owns it. Does that mean the munmap() [3] > > > will release what [1] and [2] do (allocating and replacing)? > > > > No, munmap doesn't destroy the allocator meta data. > > Should we do something to that meta data? My patch calls free on it which removes the metadata and might munmap the range (or re-use it, but that doesn't matter) Jason