I created two ioband devices and ran the dd commands only on the first
device.
From a quick look at your configuration, there seems to be no problem.
I've just posted the patches to related mailing lists. Please try it.
For the first step, my goal is to merge dm-ioband into device-mapper,
and bio-cgroup is not necessary for all situations such as bandwidth
control on a per partition basis.
I'll also try to do more test and report you back.
Thank you for your help,
Ryo Tsuruta
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