OSError: [Errno 32] Broken pipe, what's the reason? Is it because the host has not enough memory??

[Aireed]

WARNING:eth.chainservice known block block=<TransientBlock(#449 6c65537b)>
miner_2 | Traceback (most recent call last):
miner_2 | File "/usr/local/lib/python2.7/site-packages/gevent/greenlet.py", line 534, in run
miner_2 | result = self._run(_self.args, *_self.kwargs)
miner_2 | File "/usr/local/lib/python2.7/site-packages/pyethapp/eth_service.py", line 295, in _add_blocks
miner_2 | if self.chain.add_block(block, forward_pending_transactions=self.is_mining):
miner_2 | File "/usr/local/lib/python2.7/site-packages/ethereum/chain.py", line 320, in add_block
miner_2 | self._update_head(block, forward_pending_transactions)
miner_2 | File "/usr/local/lib/python2.7/site-packages/ethereum/chain.py", line 199, in _update_head
miner_2 | self.new_head_cb(block)
miner_2 | File "/usr/local/lib/python2.7/site-packages/pyethapp/eth_service.py", line 180, in _on_new_head
miner_2 | self._on_new_head_candidate() # we implicitly have a new head_candidate
miner_2 | File "/usr/local/lib/python2.7/site-packages/pyethapp/eth_service.py", line 185, in _on_new_head_candidate
miner_2 | cb(self.chain.head_candidate)
miner_2 | File "/usr/local/lib/python2.7/site-packages/pyethapp/pow_service.py", line 146, in on_new_head_candidate
miner_2 | difficulty=block.difficulty)))
miner_2 | File "/usr/local/lib/python2.7/site-packages/gipc/gipc.py", line 748, in put
miner_2 | self._write(struct.pack("!i", len(bindata)) + bindata)
miner_2 | File "/usr/local/lib/python2.7/site-packages/gipc/gipc.py", line 716, in _write
miner_2 | bytes_written = _write_nonblocking(self._fd, bindata)
miner_2 | File "/usr/local/lib/python2.7/site-packages/gevent/os.py", line 111, in nb_write
miner_2 | return _write(fd, buf)
miner_2 | OSError: [Errno 32] Broken pipe
miner_2 | <Greenlet at 0x7f02c0a372d0: <bound method ChainService._add_blocks of <ChainService at 0x7f02c381e0f0>>> failed with OSError

system info:
root@linux-ubuntu-3:/home/mime# free -m
total used free shared buffers cached
Mem: 3009 2787 221 3 14 66
-/+ buffers/cache: 2706 302
Swap: 1021 1021 0
root@linux-ubuntu-3:/home/mime#