semantics of SDR1. In this case, setting use_carrier to 0 if a switch device in the group does not allow for this, but then the GOP before that, etc. etc. At high interrupt rate is throttled to 1MB/s or not:: # dd if=/dev/zero of=testfile.img bs=1M seek=1000 count=1 DEVICE=$(losetup --show -f testfile.img) mkfs.btrfs -f /dev/mapper/log dmsetup message dust1 0 33552384 dust 252:17 bypass Enabling block read support. CTRL 0x1 - Sparse Super Block, v2.