1407ac95eSTao MaWhat:		/sys/block/<device>/iosched/target_latency
2407ac95eSTao MaDate:		March 2012
3407ac95eSTao Macontact:	Tao Ma <boyu.mt@taobao.com>
4407ac95eSTao MaDescription:
5407ac95eSTao Ma		The /sys/block/<device>/iosched/target_latency only exists
6407ac95eSTao Ma		when the user sets cfq to /sys/block/<device>/scheduler.
7407ac95eSTao Ma		It contains an estimated latency time for the cfq. cfq will
8407ac95eSTao Ma		use it to calculate the time slice used for every task.
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