On Wed, Sep 23, 2015 at 11:52:48AM +0300, Surivinta Surivinta wrote: I'm sorry but I haven't understood part of your message, but I have to reply because you ended it with "emacs" =) I don't think you need libvirt in order to transfer data that's going to be (de)compressed on-the-fly. I believe there is no need wait for all the data to be transferred when you're using libvirt's stream protocol. You'd just pipe it through (de)compression tool on each side and that should work. Of course that will not work with the APIs for which you control one side only and that would be nice to have implemented in libvirt itself, however, I have not seen any tries to do so. I haven't seen the relevant code in a while, but the change should be pretty easy.