@Christian, I haven't tried all of your combinations, but when I mount a second disk using the growpart/e2fsck/resize2fs sequence that you suggest and then mount it, it grows to 725 MB and then zerofree reports what you observed:
baccala@osito:~/NPDC/GNS3/bug$ sudo zerofree -v /dev/nbd0p1 3/5963617/6525179 But when I use an identical disk as the root filesystem, it grows to 789 MB and then zerofree reports this: baccala@osito:~/NPDC/GNS3/bug$ sudo zerofree -v /dev/nbd0p1 1524/5953550/6525179 Both virtual disks are ubuntu 20.04 cloudimgs extended to 25 GB. I used the procedure I described on May 20 (cloudinit.iso on a virtual CD-ROM) with the one disk as root and the other one as /dev/sdb. Both were identical when I booted the VM. You mentioned that "all tools that make it easy for me to deploy one also pick virtio by default"; can you run qemu from the command line on a bare metal system? If so, I thought my May 20 procedure was pretty simple. If not, then I guess it's harder to verify this. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1974100 Title: qemu ide/sata disks do not work well with discard/trim To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/qemu/+bug/1974100/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
