[libvirt-users] QEMU disk migration not using entire connection throughput

Hello everybody, I've been observing that, during the disk migration usign --copy-storage-inc, the data transfer hardly ever uses the entire available connection bandwidth (in my case 1 Gb/s), and the migration is at a non-constant speed. On the other hand, at the memory migration step, everything goes perfect. I am almost sure that this is not a nard disk throughput limitation, because a 'scp' command between the two same machines performs perfectly right. Is libvirt (or maybe QEMU?) doing some extra work that may cause slowlyness? Thanks!