On Wed, Dec 14, 2011 at 02:22:07PM -0500, Ric Wheeler wrote: > > Back at LinuxCon Prague, we talked about the new NFS and SCSI > commands that let us offload copy operations to a storage device > (like an NFS server or storage array). > > This got new life in the virtual machine world where you might want > to clone bulky guest files or ranges of blocks and was driven > through the standards bodies by vmware, microsoft and some of the > major storage vendors. Windows8 has this functionality fully coded > and integrated in the GUI, I assume vmware also uses it and there > are some vendors who announced support at the SNIA SDC conference. > > We had an active thread a couple of years back that came out of the > reflink work and, at the time, there seemed to be moderately > positive support for adding a new system call that would fit this > use case (Joel Becker's copyfile()). > > Can we resurrect this effort? Is copyfile() still a good way to go, > or should we look at other hooks? Windows uses a COPYCHUNK call, which specifies the following parameters: Definition of a copy "chunk": hyper source_off; hyper target_off; uint32 length; and an array of these chunks which is passed into their kernel. This is what we have to implement in Samba. Jeremy. -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
