BEAM's default allocator settings will allocate often. It's just how the VM works. The erlang allocation framework: http://erlang.org/doc/man/erts_alloc.html ht

BEAM's default allocator settings will allocate often. It's just how the VM works. The erlang allocation framework: http://erlang.org/doc/man/erts_alloc.html http://erlang.org/doc/man/erts_alloc.html is a complicated beast. We were able to simulate this failure condition synthetically by inducing memory bandwidth pressure on the guest VM. We noticed that during certain periods of time, not caused by any workload we ran, the time spent doing malloc/mmap would 10-20x, but the # of calls would not.