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Provide another source where to read the information in >>> /sys/fs/btrfs/FSID/devinfo/DEVID/stats . >> >> The planned stat here is errors stat. >> So why not rename this to error_stats? > > I think it's commonly called device stats, dev stats, so when it's in > 'devinfo' it's like it's the 'stats' for the device. > We don't have other > stats, like regarding io but in that case it would make sense to > distnguish the names. My read_policy work (which I suppose is next on your list for review) made sense that publishing the io-stat information locally from btrfs is a good idea. So that it provides clarity if the IO is skewed to a device or balanced. Which is even more essential in the case of mixed device types. For now IMHO, /sys/fs/btrfs/FSID/devinfo/DEVID/error_stats is harmless. Thanks, Anand