On 03/28/2013 02:49 PM, Anand Avati wrote: > Yes, it should, based on the theory of how ext4 was generating the > 63bits. But Jeff's test finds that the experiment is not matching the > theory. FWIW, I was able to re-run my test in between stuff related to That Other Problem. What seems to be happening is that we read correctly until just after d_off 0x4000000000000000, then we suddenly wrap around - not to the very first d_off we saw, but to a pretty early one (e.g. 0x0041b6340689a32e). This is all on a single brick, BTW, so it's pretty easy to line up the back-end and front-end d_off values which match perfectly up to this point. I haven't had a chance to ponder what this all means and debug it further. Hopefully I'll be able to do so soon, but I figured I'd mention it in case something about those numbers rang a bell.
