On Mon, Apr 02, 2007 at 03:27:39PM -0700, Anton B. Rang wrote: > > > All file systems provide writes by default which are > > > atomic with respect to readers of the file. > > > > Surely, only in the absence of a crash - otherwise, > > POSIX would require implementation of transactional > > write semantics in all file systems. Or is that what > > you meant by the last sentence in your post? > > Well, that's part of what I meant, but the actual POSIX requirement is > that a read which occurs while a write is in progress cannot see a > partially-completed write. A system crash would tend to stop any > writes in progress, so this particular requirement doesn't seem to > apply. :-)
Richard seems to care about the O_APPEND case. Can you address that? IIRC O_APPEND writes are atomic w.r.t. each other up to some write size (meaning that for larger append writes two appends can end up interleaving in chunks of the atomic append write size limit). Nico -- _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
