Kai Krakow posted on Mon, 04 Apr 2016 02:00:43 +0200 as excerpted: > Does this also implement "copy-back" - thus, it returns the hot-spare > device to global hot-spares when the failed device has been replaced?
I don't believe it does that in this initial implementation, anyway. There's a number of issues with the initial implementation, including the fact that the hot-spare is global only and can't be specifically assigned to a filesystem or set of filesystems, which means, if you have multiple filesystems using different sized devices, the hot-spares must be sized to match the largest device they could replace, and thus would be mostly wasted if they ended up replacing a far smaller device. If the spares could be associated with specific filesystems, then specifically sized spares could be associated appropriately, avoiding that waste. Additionally, it would then be possible to queue up say 20 spares on an important filesystem, with no spares on another that you'd rather just go down if a device fails. So obviously the initial implementation isn't seriously enterprise-ready and is sub-optimal in many ways, but it's better than what is currently available (no automated spare handling at all), and an implementation must start somewhere, so as long as it's designed to be improved and extended with the missing features over time, as has been indicated, it's a reasonable first-implementation. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
