> > zeros, while a cp --reflink will create a sparse file, though? > > Well see therein lies the problem. The documentation for cp states: > > "When --reflink[=always] is specified, perform a lightweight copy, where > the data blocks are copied only when modified." > > The lightest weight copy for a bunch of zeroes is a hole. That's the > interpretation I went with. :) > > OTOH the "copied only when modified" language does sort of imply that > you'd share the unwritten extents and then COW them, but that involves > adding more machinery to _iomap_begin to copy-write over zeroes, > which seems pointless and would involve a format change since old > kernels wouldn't know to check for shared unwritten extents... > > ...and if your worry is about being able to write to tmp3 without > hitting ENOSPC then you'll have to fallocate + funshare the file > separately anyway. /me should read the whole thread before replying to earlier messages :P > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Carlos -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
