The function op_is_discardable introduces lock overhead which can

The function op_is_discardable introduces lock overhead which can
The function op_is_discardable introduces lock overhead which can
not be ignored.It would be better to judge if to discard op when
the connection disconnected as a parameter whether the network is
believable or extremely unlikelihood.

add g_conf osd_discard_disconnected_ops to control whether to
discard op when the connection disconnected
Waiting for test

Signed-off-by: ZhenyuLeng <lengzhenyu@ict.ac.cn>