Chris Murphy posted on Thu, 19 Mar 2015 13:09:06 -0600 as excerpted: > Erkki's cp --reflink idea is a good one. I've often wondered if it's a > good idea, and possible, to eventually make --reflink the default > behavior with Btrfs copies (I think some things probably first need > enhancement like the cross subvolume stuff, because otherwise cp could > fail inexplicably).
If cp --reflink=auto was the default, it'd "just work", making a reflink where possible, falling back to a normal copy where not possible to reflink. However, I'd be wary of such a change, because admins are used to cp creating a separate copy which may well be intended as a backup, guarding against I/O errors on the original. Btrfs does do checksum checking to ensure validity, but if that fails, do you really want it failing for BOTH copies, including the one the admin made specifically to AVOID such a problem, because he knows the file is likely to be open at the time of a crash or some such and did a cp to have a backup, just in case? I know as an admin, *I* wouldn't like such behavior. Far better to simply have the option there should I deliberately invoke it, but not invoke it by default, in ordered to avoid unhappy surprises! -- 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
