Hello again. As I mentioned in my previous mail, I am not yet using BTRFS for my real data. I'd like to know a few more things before doing so. Per my understanding of snapshots, unless I specifically mount the subvolume and make changes to it, its contents will not change. However, my understanding of nocow setting via chattr +C seems to indicate that files marked with nocow are updated in place, which means that if two snapshots point to the same file, if the contents are modified via one snapshot, then it would change the other file, which contradicts with the definition of a snapshot. I tried this out, and sure enough, just because chattr +C was applied, my change in the snapshot did not reflect in the original subvolume. So nocow via chattr +C only means "don't do COW unless this file exists in another snapshot", right? -- Shriramana Sharma ஶ்ரீரமணஶர்மா श्रीरमणशर्मा -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html