Anthony Liguori <anth...@codemonkey.ws> writes: > Rusty Russell <ru...@rustcorp.com.au> writes: > >> "Michael S. Tsirkin" <m...@redhat.com> writes: >> >> No, because I don't understand it. Is it true for the case of >> virtio_blk, which has outstanding requests? >> >>>> Currently we dump a massive structure; it's inelegant at the very >>>> least. > > Inelegant is a kind word.. > > There's a couple things to consider though which is why this code hasn't > changed so far. > > 1) We're writing native endian values to the wire. This is seriously > broken. Just imagine trying to migrate from qemu-system-i386 on an > big endian box to a little endian box. > > 2) Fixing (1) either means (a) breaking migration across the board > gracefully or (b) breaking migration on [big|little] endian hosts in > an extremely ungraceful way. > > 3) We send a ton of crap over the wire that is unnecessary, but we need > to maintain it. > > I wrote up a patch series to try to improve the situation that I'll send > out. I haven't gotten around to testing it with an older version of > QEMU yet. > > I went for 2.b and choose to break big endian hosts.
Since we only actually want to save the descriptor head, I was planning on a new format version. That will fix both... Look forward to your patch, Rusty.
