You have been subscribed to a public bug: This report is moved from systemd to here: https://github.com/systemd/systemd/issues/16242
A qemu-nbd device reports that it can discard a lot of bytes: cat /sys/block/nbd0/queue/discard_max_bytes 2199023255040 And indeed, discard works with small images: $ qemu-img create -f qcow2 /tmp/image.img 2M $ sudo qemu-nbd --connect=/dev/nbd0 /tmp/image.img $ sudo blkdiscard /dev/nbd0 but not for bigger ones (still smaller than discard_max_bytes): $ qemu-img create -f qcow2 /tmp/image.img 5G $ sudo qemu-nbd --connect=/dev/nbd0 /tmp/image.img $ sudo blkdiscard /dev/nbd0 ** Affects: qemu Importance: Undecided Status: New -- qemu-nbd fails to discard bigger chunks https://bugs.launchpad.net/bugs/1884831 You received this bug notification because you are a member of qemu-devel-ml, which is subscribed to QEMU.