Issue 1:
When I run ansible-playbook on HEAD, I get the following traceback:

TASK: [Check known pacnews] ***************************************************
ok: [grego] => (item={'path': '/etc/fstab', 'old': '4ebaee2c67a0e6df3def1fbd8ce5194d07ca6546', 'new': 'a805082718eb9814229968ab11be76a8d34d6033', 'keep': 'old'})
changed: [grego] => (item={'path': '/etc/pacman.d/mirrorlist', 'old': '162f45764216fe0cc2697c5ca63f901032f26ea6', 'new': 'ANY', 'keep': 'old'})
ok: [grego] => (item={'path': '/etc/shadow', 'old': 'ANY', 'new': 'e0d59e5430b4dd9c6ed721e29de450487d4ad89f', 'keep': 'old'})
ok: [grego] => (item={'path': '/etc/gshadow', 'old': '1dbb1d43b8c1854898589bb6d1ea92d49be508c6', 'new': 'c96a71de4466893f090905f536f418ddac708e71', 'keep': 'old'})
ok: [grego] => (item={'path': '/etc/passwd', 'old': '110262be0777e00239aa9413eba1bd9f8e82e84c', 'new': '5db8ef768aa79940d0c28347ebfa8755cfb53920', 'keep': 'old'})
ok: [grego] => (item={'path': '/etc/group', 'old': 'fe85b1c169d6ecff70868e05d762dd7528f65e7c', 'new': '27d785a76a1e5c61f691ce2bbc3cbe441310b7c2', 'keep': 'old'})
ok: [grego] => (item={'path': '/etc/locale.gen', 'old': '13d6ce49547f3bd457364983fab74b254569dd90', 'new': '5672ef37a399b86ef417fa42155777e93840dd53', 'keep': 'new'})
ok: [grego] => (item={'path': '/etc/pacman.conf', 'old': 'd5825b3d61c7e71f16c8790af1cb0a2c429bbff6', 'new': '3c1bddf27602e02fb57801c0ea7313b3869acc92', 'keep': 'old'})
ok: [grego] => (item={'path': '/boot/grub/grub.cfg', 'old': 'NONE', 'new': '5b7fcb0718a23035c039eb2fda9e088bb13ae611', 'keep': 'new'})
ok: [grego] => (item={'path': '/etc/mkinitcpio.conf', 'old': '67ca9a323c979ee93c4c1a5592b02c89564d630e', 'new': 'c27c0ae5797582f47f8db1368fc730658c8d4cfe', 'keep': 'new'})
fatal: [grego] => Traceback (most recent call last):
File "/usr/local/brew/lib/python2.7/site-packages/ansible/runner/__init__.py", line 368, in _executor
exec_rc = self._executor_internal(host, new_stdin)
File "/usr/local/brew/lib/python2.7/site-packages/ansible/runner/__init__.py", line 481, in _executor_internal
complex_args=complex_args
File "/usr/local/brew/lib/python2.7/site-packages/ansible/runner/__init__.py", line 612, in _executor_internal_inner
tmp = self._make_tmp_path(conn)
File "/usr/local/brew/lib/python2.7/site-packages/ansible/runner/__init__.py", line 736, in _make_tmp_path
result = self._low_level_exec_command(conn, cmd, None, sudoable=False)
File "/usr/local/brew/lib/python2.7/site-packages/ansible/runner/__init__.py", line 671, in _low_level_exec_command
rc, stdin, stdout, stderr = conn.exec_command(cmd, tmp, sudo_user, sudoable=sudoable, executable=executable)
File "/usr/local/brew/lib/python2.7/site-packages/ansible/runner/connection_plugins/ssh.py", line 165, in exec_command
stdout=subprocess.PIPE, stderr=subprocess.PIPE)
File "/usr/local/brew/Cellar/python/2.7.5/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 703, in __init__
errread, errwrite) = self._get_handles(stdin, stdout, stderr)
File "/usr/local/brew/Cellar/python/2.7.5/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 1120, in _get_handles
errread, errwrite = self.pipe_cloexec()
File "/usr/local/brew/Cellar/python/2.7.5/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 1153, in pipe_cloexec
r, w = os.pipe()
OSError: [Errno 24] Too many open files

Here's that task:

- name: Check known pacnews
pacnew: >
path={{item.path}}
new={{item.new}}
old={{item.old}}
keep={{item.keep}}
with_items: pacnews

It's using my pacnew module: https://github.com/akerl/archer/blob/master/library/pacnew

The full plays and such are here:

https://github.com/akerl/archer

I traced this issue down to 4d1f447, and confirmed it doesn't occur in baffa8d. My test runs are here:

https://gist.github.com/akerl/6584034

Somebody in #ansible suggested I use "-f 1", which I tried; the issue was the same. That run is in the gist as well.

Issue 2:
It seems some recent changes has introduced this regression, this occurs on OSX 10.7, bumping up the limits by "ulimit -n 2048" works around the problem. There might just be some file descriptors/pipes not being closed. You could limit the loop (wherever its happening) for the subprocesses to be just 1024?

I might poke around if I have time. For now the above is a bug report!

TASK: [clone {{host_group}} code - private head] ******************************
fatal: [10.0.1.200] => Traceback (most recent call last):
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/ansible/runner/__init__.py", line 368, in _executor
exec_rc = self._executor_internal(host, new_stdin)
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/ansible/runner/__init__.py", line 455, in _executor_internal
return self._executor_internal_inner(host, self.module_name, self.module_args, inject, port, complex_args=complex_args)
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/ansible/runner/__init__.py", line 612, in _executor_internal_inner
tmp = self._make_tmp_path(conn)
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/ansible/runner/__init__.py", line 736, in _make_tmp_path
result = self._low_level_exec_command(conn, cmd, None, sudoable=False)
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/ansible/runner/__init__.py", line 671, in _low_level_exec_command
rc, stdin, stdout, stderr = conn.exec_command(cmd, tmp, sudo_user, sudoable=sudoable, executable=executable)
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/ansible/runner/connection_plugins/ssh.py", line 165, in exec_command
stdout=subprocess.PIPE, stderr=subprocess.PIPE)
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 703, in __init__
errread, errwrite) = self._get_handles(stdin, stdout, stderr)
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 1120, in _get_handles
errread, errwrite = self.pipe_cloexec()
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 1153, in pipe_cloexec
r, w = os.pipe()
OSError: [Errno 24] Too many open files

FATAL: all hosts have already failed -- aborting