On Wed, Jan 2, 2013 at 11:18 AM, Troy Benjegerdes <ho...@hozed.org> wrote: > If you do get a hash collision, it's a rather exceptional event, so I'd > say every effort should be made to log the event and the data that created > it in multiple places. > > There are three questions I'd ask on a hash collision: > > 1) was it the data? > 2) was it the hardware? > 3) was it a software bug?
Yes, that is probably good too, and saving off the old and new block content that collided. Unless you are checksumming the blocks, I suspect that the most common reason for "collisions" would just be cases where the original block was corrupted/changed on disk and you dont detect it and then when you re-write an identical one the blocks no longer match and thus you get a false collision.
