performance: 0.996 graphic: 0.977 network: 0.956 device: 0.890 ppc: 0.857 PID: 0.780 semantic: 0.756 debug: 0.737 socket: 0.731 architecture: 0.712 vnc: 0.705 VMM: 0.702 hypervisor: 0.674 risc-v: 0.669 x86: 0.636 mistranslation: 0.624 i386: 0.618 permissions: 0.609 KVM: 0.555 register: 0.551 kernel: 0.548 peripherals: 0.545 arm: 0.517 TCG: 0.514 user-level: 0.463 boot: 0.419 assembly: 0.331 virtual: 0.178 files: 0.168 live migration's performance with compression enabled is much worse than compression disabled Description of problem: Steps to reproduce: 1. Run QEMU the Guests with 1Gpbs network on source host and destination host with QEMU command line 2. Run some memory work loads on Guest, for example, ./memtester 1G 1 3. Set migration parameters in QEMU monitor. On source and destination, execute: #migrate_set_capability compress on Other compression parameters are all default. 4. Run migrate command, # migrate -d tcp:10.156.208.154:4000 5. The results: - without compression: total time: 197366 ms throughput: 937.81 mbps transferred Ram: 22593703 kbytes - with compression: total time: 281711 ms throughput: 90.24 mbps transferred Ram: 3102898 kbytes When compression is enabled, the compression transferred ram is reduced a lot. But the throughput is down badly. The total time of live migration with compression is longer than without compression. I tried with 100G network bandwidth, it also has the same problem. Additional information: