While using `guix system vm`, I noticed this warning. I think it's new, maybe from the 5.2.0 update? ------ qemu-system-x86_64: warning: 9p: degraded performance: a reasonable high msize should be chosen on client/guest side (chosen msize is <= 8192). See https://wiki.qemu.org/Documentation/9psetup#msize for details. ------ That web page suggests that we increase the virtio packet size when declaring the 9p file-systems, I think in %linux-vm-file-systems of (gnu system vm).