On Mar 14, 2013, at 4:10 PM, Roman Mamedov [off-list ref] wrote:

- shouldn't the reads have been quietly satisfied my md3 from sdf1, instead of just passing the buck^W error
 due to unreadable sdg1 to the higher (filesystem) layer?

What distro kernel and version?

Since you're not using btrfs raid1 there isn't a second copy maintained by btrfs itself, so it can't fix this. It's reporting a checksum failure for the single copy of data on the md raid1. It is getting the data elsewhere but it's btrfs saying that the checksum doesn't match.

Chris Murphy