27 lines
		
	
	
	
		
			694 B
			
		
	
	
	
		
			Text
		
	
	
	
	
	
		
		
			
		
	
	
			27 lines
		
	
	
	
		
			694 B
			
		
	
	
	
		
			Text
		
	
	
	
	
	
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								dm-delay
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								========
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								Device-Mapper's "delay" target delays reads and/or writes
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								and maps them to different devices.
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								Parameters:
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								    <device> <offset> <delay> [<write_device> <write_offset> <write_delay>]
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								With separate write parameters, the first set is only used for reads.
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								Delays are specified in milliseconds.
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								Example scripts
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								===============
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								[[
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								#!/bin/sh
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								# Create device delaying rw operation for 500ms
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								echo "0 `blockdev --getsize $1` delay $1 0 500" | dmsetup create delayed
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								]]
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								[[
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								#!/bin/sh
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								# Create device delaying only write operation for 500ms and
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								# splitting reads and writes to different devices $1 $2
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								echo "0 `blockdev --getsize $1` delay $1 0 0 $2 0 500" | dmsetup create delayed
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								]]
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