I just pushed out some "lazy io" patches to the unstable branches. Lazy io is enabled on a file handle via a ceph ioctl (CEPH_IOC_LAZYIO). Once that happens, an application can do buffered reads/writes even when a file is open on multiple clients, and is responsible for managing it's own cache conherency between nodes.
An application can flush dirty data using sync_file_range(2), and invalidate cached data using posix_fadvise(2) (POSIX_FADV_DONTNEED). These are equivalent to the lazyio_propagate(2) and lazyio_synchronise(2) in the original O_LAZY proposal from the POSIX IO group way back when. If anybody is interested in testing this functionality, let us know! sage -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
