errors regarding ansible task execution on multiple hosts

hello,
i am having currently 150 hosts.In ansible i have known that exeution of task in multiple hosts can be set by the forks parameter.Initially i have set the forks =70 and i run the following command:

ansible -m shell -a “date” all

it works fine. But while i put forks=100 it throws the following errors.

Traceback (most recent call last):
File “/usr/lib/pymodules/python2.7/ansible/runner/init.py”, line 85, in _executor_hook
result_queue.put(return_data)
File “”, line 2, in put
File “/usr/lib/python2.7/multiprocessing/managers.py”, line 758, in _callmethod
conn.send((self._id, methodname, args, kwds))
IOError: [Errno 32] Broken pipe
Process Process-16:
Traceback (most recent call last):
File “/usr/lib/python2.7/multiprocessing/process.py”, line 258, in _bootstrap
self.run()
File “/usr/lib/python2.7/multiprocessing/process.py”, line 114, in run
self._target(*self._args, **self._kwargs)
File “/usr/lib/pymodules/python2.7/ansible/runner/init.py”, line 81, in _executor_hook
while not job_queue.empty():
File “”, line 2, in empty
File “/usr/lib/python2.7/multiprocessing/managers.py”, line 758, in _callmethod
conn.send((self._id, methodname, args, kwds))
IOError: [Errno 32] Broken pipe
vltr619 | success | rc=0 >>
Wed Sep 23 19:21:22 IST 2015

Traceback (most recent call last):
File “/usr/lib/pymodules/python2.7/ansible/runner/init.py”, line 85, in _executor_hook
result_queue.put(return_data)
File “”, line 2, in put
File “/usr/lib/python2.7/multiprocessing/managers.py”, line 758, in _callmethod
conn.send((self._id, methodname, args, kwds))
IOError: [Errno 32] Broken pipe
Process Process-83:
Traceback (most recent call last):
File “/usr/lib/python2.7/multiprocessing/process.py”, line 258, in _bootstrap
self.run()
File “/usr/lib/python2.7/multiprocessing/process.py”, line 114, in run
self._target(*self._args, **self._kwargs)
File “/usr/lib/pymodules/python2.7/ansible/runner/init.py”, line 81, in _executor_hook
while not job_queue.empty():
File “”, line 2, in empty
File “/usr/lib/python2.7/multiprocessing/managers.py”, line 758, in _callmethod
conn.send((self._id, methodname, args, kwds))
IOError: [Errno 32] Broken pipe

I am not sure why these errors occur.Could you please give an idea regarding this error?

the following are my virtualmachine configuration details
ansible version is 1.9.2
python version is 2.7.6
1 GB ram
1 core processor
server provider is digital ocean.
ubuntu 14.04 OS