We did some performance tests  for LVM and BDD drivers. All tests were
executed on real hardware with OpenStack Mitaka release. Unfortunately, we
didn't have enough time to execute all tests and compare results. We used
Sahara/Hadoop cluster with TestDFSIO and others tests.
All tests were executed on the same hardware and OpenStack release. Only
difference were in cinder.conf to enable needed backend and/or target
Tests were executed on following configurations:
- LVM +TGT target
- LVM+LocalTarget: PoC based on  spec
- Block Device Driver.
Feel free to ask question if any about our testing infrastructure,
OpenStack Development Mailing List (not for usage questions)