dm-delay
Device-Mapper’s “delay” target delays reads and/or writes
and maps them to different devices.
Parameters:
With separate write parameters, the first set is only used for reads.
Delays are specified in milliseconds.
Example scripts
[[
#!/bin/sh
Create device delaying rw operation for 500ms
echo “0 blockdev --getsize $1 delay $1 0 500” | dmsetup create delayed
]]
[[
#!/bin/sh
Create device delaying only write operation for 500ms and
splitting reads and writes to different devices $1 $2
echo “0 blockdev --getsize $1 delay $1 0 0 $2 0 500” | dmsetup create delayed
]]
