Commit | Line | Data |
---|---|---|
26b9f228 HM |
1 | dm-delay |
2 | ======== | |
3 | ||
4 | Device-Mapper's "delay" target delays reads and/or writes | |
5 | and maps them to different devices. | |
6 | ||
7 | Parameters: | |
8 | <device> <offset> <delay> [<write_device> <write_offset> <write_delay>] | |
9 | ||
10 | With separate write parameters, the first set is only used for reads. | |
11 | Delays are specified in milliseconds. | |
12 | ||
13 | Example scripts | |
14 | =============== | |
15 | [[ | |
16 | #!/bin/sh | |
17 | # Create device delaying rw operation for 500ms | |
18 | echo "0 `blockdev --getsize $1` delay $1 0 500" | dmsetup create delayed | |
19 | ]] | |
20 | ||
21 | [[ | |
22 | #!/bin/sh | |
23 | # Create device delaying only write operation for 500ms and | |
24 | # splitting reads and writes to different devices $1 $2 | |
25 | echo "0 `blockdev --getsize $1` delay $1 0 0 $2 0 500" | dmsetup create delayed | |
26 | ]] |