162306a36Sopenharmony_ciWhat:		/sys/block/<device>/iosched/target_latency
262306a36Sopenharmony_ciDate:		March 2012
362306a36Sopenharmony_cicontact:	Tao Ma <boyu.mt@taobao.com>
462306a36Sopenharmony_ciDescription:
562306a36Sopenharmony_ci		The /sys/block/<device>/iosched/target_latency only exists
662306a36Sopenharmony_ci		when the user sets cfq to /sys/block/<device>/scheduler.
762306a36Sopenharmony_ci		It contains an estimated latency time for the cfq. cfq will
862306a36Sopenharmony_ci		use it to calculate the time slice used for every task.
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