l...@gnu.org (Ludovic Courtès) writes: > Hi Chris, > > Christopher Baines <m...@cbaines.net> skribis: > >> 1.13 0.000019 0 3853 openat > > [...] > >> 13.56 0.193014 50 3853 openat > > So openat(2) is 4 orders of magnitude slower in the VM, which is a > problem. > > I guess a large part of that is due to the fact that VM created with > ‘guix system vm’ use unionfs as their root file system, which is a FUSE > thing (see the “volatile” options in (gnu system vm), (gnu system > linux-initrd), and (gnu build linux-boot).) I’m not sure how we could > avoid it.
We might switch to the linux kernel's bultin overlayfs, which should be faster. https://wiki.archlinux.org/index.php/Overlay_filesystem
