Some more details about this experiment: The host is running Ubuntu-16.04 with 4.4.0 Linux kernel and QEMU-2.5.1; The guest is running Ubuntu-12.04, except Memcached with Ubuntu-16.04.
The exact numbers of the proportions of write-not-dirty pages for the first 2 pre-copy iterations: (0.445 means 44.5%) Memcached: 0.445, 0.478 Zeusmp: 0.670, 0.727 Mcf: 0.808, 0.793 Bzip2: 0.464, 0.447 Milc: 0.341, 0.037 cactusADM: 0.280, 0.248 lbm: 0.090, 0.037 GemsFDTD: 0.226, 0.172 Bwaves: 0.069, 0.003 Astar: 0.113, 0.039 Xalancbmk: 0.082, 0.041 Wrf: 0.141, 0.073 Any advice? Looking forward to any response. Thank you. Chunguang