На какие цели portage при обновлении съедает всю память?

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* Manifest timestamp: 2018-11-02 22:38:39 UTC
 * Valid OpenPGP signature found:
 * - primary key: DCD05B71EAB94199527F44ACDB6B8C1F96D8BF6D
 * - subkey: E1D6ABB63BFCFB4BA02FDF1CEC590EEAC9189250
 * - timestamp: 2018-11-02 22:38:39 UTC
 * Verifying /usr/portage/.tmp-unverified-download-quarantine ...                                                                                                                                                  [ ok ]
Traceback (most recent call last):
  File "/usr/lib64/python2.7/site-packages/portage/util/_async/AsyncFunction.py", line 39, in _run
    result = self.target(*(self.args or []), **(self.kwargs or {}))
  File "/usr/lib64/python2.7/site-packages/portage/sync/controller.py", line 168, in sync
    taskmaster.run_tasks(tasks, func, status, options=task_opts)
  File "/usr/lib64/python2.7/site-packages/portage/sync/controller.py", line 67, in run_tasks
    result = getattr(inst, func)(**kwargs)
  File "/usr/lib64/python2.7/site-packages/portage/sync/syncbase.py", line 253, in sync
    return self.update()
  File "/usr/lib64/python2.7/site-packages/portage/sync/modules/rsync/rsync.py", line 458, in update
    self._remove_download(download_dir)
  File "/usr/lib64/python2.7/site-packages/portage/sync/modules/rsync/rsync.py", line 108, in _remove_download
    exitcode = subprocess.call(['rm', '-rf', download_dir])
  File "/usr/lib64/python2.7/subprocess.py", line 172, in call
    return Popen(*popenargs, **kwargs).wait()
  File "/usr/lib64/python2.7/subprocess.py", line 394, in __init__
    errread, errwrite)
  File "/usr/lib64/python2.7/subprocess.py", line 938, in _execute_child
    self.pid = os.fork()
OSError: [Errno 12] Cannot allocate memory

Action: sync for repo: gentoo, returned code = 1