Hi, On 5/14/19 4:28 PM, Roman Penyaev wrote: > On 2019-04-17 23:53, Manuel Bentele wrote: > > [cut] > >> If you have an idea to solve the opposition for file formats that are >> acting as a container or virtual disk node for various data, please let >> me know. > > If you need a raw block device you can export qcow2 image as a network > block > device, something as the following: > > # modprobe nbd > # qemu-nbd --connect=/dev/nbd0 image.qcow2 > # fdisk -l /dev/nbd0 > > I suppose simplest variant. > > -- > Roman
Thanks for your suggestion. We already discussed this during a project meeting. Some time ago, I have summarized that already (sorry for the diverging conversation of this topic on the mailinglist). All in all, the crucial point is the performance: > [...] > > A workaround for that problem could be the local usage of nbd to include > the QCOW2 disk image as block device, but it involves a lot of > interaction between user and kernel space and thus an decreasing > performance. That leads to the motivation to implement the reading of > QCOW2 disk images directly in the kernel and aim for an merge into the > mainline kernel source to avoid out-of-kernel-tree maintenance. > > [...] -- Manuel
