4 ms·

So how is memory fragmentation avoided?

• pjc50 5y ago
  That's a question for the underlying allocator, surely? (Quite often the answer is "it isn't")
  • andi999 5y ago
    Not just for the allocator. I always thought a main point of a garbage collector was heap compactification (shuffling things around so there is more space), but maybe I am wrong.
    • xxs 5y ago
      Not every GC has compaction phase though, but generational ones do by design.
    • cmrdporcupine 5y ago
      Nah, only copying / generational collectors do heap compactification. A simple Mark&Sweep collector doesn't, for example. Nor does reference counting. Both of which are used by many Lisp or Lisp-like languages. Nothing can substitute for a really good allocator.
      • andi999 5y ago
        So what happens to long running lisp programs? Running out of memory due to fragmentation eventually?
        • xxs 5y ago
          One would expect at least a provision for a stop the world phase. where all mutator threads get to wait for a massive defragmentation.