Here's an example error from two concurrent emerge --sync operations interfering with each other: > # running emerge --sync > > rm: cannot remove '/var/portage/repos/gentoo/.tmp-unverified-download-quarantine': Directory not empty > Traceback (most recent call last): > File "/usr/lib64/python3.6/site-packages/portage/util/_async/AsyncFunction.py", line 39, in _run > result = self.target(*(self.args or []), **(self.kwargs or {})) > File "/usr/lib64/python3.6/site-packages/portage/sync/controller.py", line 169, in sync > taskmaster.run_tasks(tasks, func, status, options=task_opts) > File "/usr/lib64/python3.6/site-packages/portage/sync/controller.py", line 68, in run_tasks > result = getattr(inst, func)(**kwargs) > File "/usr/lib64/python3.6/site-packages/portage/sync/syncbase.py", line 304, in sync > return self.update() > File "/usr/lib64/python3.6/site-packages/portage/sync/modules/rsync/rsync.py", line 333, in update > dosyncuri, timestamp, opts) > File "/usr/lib64/python3.6/site-packages/portage/sync/modules/rsync/rsync.py", line 705, in _do_rsync > command.append(self.download_dir) > File "/usr/lib64/python3.6/site-packages/portage/sync/syncbase.py", line 125, in download_dir > self._download_dir = self.repo_storage.init_update() > File "/usr/lib64/python3.6/site-packages/portage/util/futures/_sync_decorator.py", line 21, in wrapper > return loop.run_until_complete(func(*args, **kwargs)) > File "/usr/lib64/python3.6/site-packages/portage/util/_eventloop/EventLoop.py", line 833, in run_until_complete > return future.result() > File "/usr/lib64/python3.6/site-packages/portage/util/futures/compat_coroutine.py", line 113, in _next > future = self._generator.throw(previous.exception()) > File "/usr/lib64/python3.6/site-packages/portage/repository/storage/hardlink_quarantine.py", line 58, in init_update > yield self._check_call(['rm', '-rf', update_location]) > File "/usr/lib64/python3.6/site-packages/portage/util/futures/compat_coroutine.py", line 111, in _next > future = self._generator.send(previous.result()) > File "/usr/lib64/python3.6/site-packages/portage/repository/storage/hardlink_quarantine.py", line 53, in _check_call > format(p.returncode, ' '.join(cmd))) > portage.repository.storage.interface.RepoStorageException: command exited with status 1: rm -rf /var/portage/repos/gentoo/.tmp-unverified-download-quarantine
We could have a single global lock, or separate locks for each repository. If we have separate locks then we have to lock the master(s) of a given repository while it's syncing, and the order of acquiring locks has to be predictable in order to avoid deadlocks.
