bmaptool vs dd

voodoo@hades:/opt/images$ time sudo bmaptool copy --bmap bone.bmap
bone-debian-7.8-lxde-4gb-armhf-2015-03-01-4gb.img /dev/sdd
bmaptool: info: block map format version 2.0
bmaptool: info: 947200 blocks of size 4096 (3.6 GiB), mapped 485153
blocks (1.9 GiB or 51.2%)
bmaptool: info: copying image
'bone-debian-7.8-lxde-4gb-armhf-2015-03-01-4gb.img' to block device
'/dev/sdd' using bmap file 'bone.bmap'
bmaptool: info: 100% copied
bmaptool: info: synchronizing '/dev/sdd'
bmaptool: info: copying time: 2m 47.4s, copying speed 11.3 MiB/sec

real 2m47.717s
user 0m9.100s
sys 0m4.032s


voodoo@hades:/opt/images$ time sudo dd
if=bone-debian-7.8-lxde-4gb-armhf-2015-03-01-4gb.img of=/dev/sdd
7577600+0 records in
7577600+0 records out
3879731200 bytes (3.9 GB) copied, 1013.02 s, 3.8 MB/s

real 16m54.992s
user 0m4.384s
sys 1m2.072s

Has anyone fully tested bmaptool?


First I’ve “heard” of it. Seems like a good find though. If you’re wanting someone to test an eMMC flash image though, I’d be willing to try on an A5A( 2 GB). So long as it does not permanently ruin the board.

It seems to work pretty good, for existing image just:

bmaptool create -o bone.bmap bone.img

sudo bmaptool copy --bmap image.bmap bone.img /dev/sdg

I enabled the *.bmap file generation by default:

So user can take advantage of this..


I’ll have to read up on it first probably. The syntax doesn’t make sense to me yet. Usually, I prefer to understand things before I use them.

Been working “hard” reversing a proprietary NEMA 2000 protocol, and writing code to display the data I’m reading off the CANBus . . . so no telling when I’ll get around to it. Huge learning experience for me, and I’m no where near done learning. Luckily for me, Wulfman did most of the protocol reversing by hand, so I have something to compare things to.

Can’t help but wonder if this( bmaptool ) will help solve the problems some people have been experiencing when trying to flash new images to the eMMC. I would imagine ( perhaps wrongly ) that’s where your motivation lies. Come to think of it, I’ve never had this problem personally, because I’ve never flashed either of the 2 BBB’s I have with me. I should almost write a book on how not to use the eMMC heh.

Still if you need help testing, just let me know.