Unable to install Fedora 26 Alpha from DVD media

[Panos Kavalagios]

Attempting to install the F26 Alpha from the following media in a new created VM:

​https://download.fedoraproject.org/pub/fedora/linux/releases/test/26_Alpha/Workstation/x86_64/iso/Fedora-Workstation-Live-x86_64-26_Alpha-1.7.iso

is impossible. The VM either is extremely slow consuming all CPU power. In some attempts the login process was interrupt and the user was logged out again and the mouse disappeared.

[Frank Mehnert]

And if you disable 3D in the VM settings?

[Frank Mehnert]

Also, you assign 4 VCPUs on a box which has 4 physical cores. Better try with less VCPUs. Keep in mind that there is overhead for the virtualization and that other host applications need CPU time as well.

[Panos Kavalagios]

Disabling 3D has no effect. I forgot to add it in my initial description.

I usually prefer to have the full available CPU power in the VM, but if you believe that might be a problem, I will try with less assigned CPUs.

[Panos Kavalagios]

I have assigned 2 VCPUs and it only lowered the CPU consumption by half. It still does not display the installer after several minutes.

[Frank Mehnert]

Well, I see that the guest boots quite slow, even with 1 VCPU. During the boot process the DVD icon is green for a long time (showing read access to the medium). But I don't think this is a VirtualBox problem. From experiences with older Fedora releases I know that these guys enable all kind of kernel sanity checks during the Alpha/Beta release cycle. And many of these sanity checks have a performance impact.

Also: While the Live DVD is booting I had a look at the session information: Even if I tell the guest to boot directly without doing a medium check the guest is reading and reading. After hitting the login button I stayed for a longer while but after the guest read more than 10GB from the (virtual) DVD drive I aborted. Looks to me like some Fedora 26 Alpha bug...

[Frank Mehnert]

Actually it's the guest RAM size. The default for Fedora is 1GB. That's not enough for Fedora 26. Better use 2GB. It's not that easy to increase the default RAM size for Fedora guests because older guests require much less RAM. The OS defaults for Linux distributions (Fedora / Ubuntu / Debian etc) are too coarse grained because they don't include any distribution version number. We plan to change this eventually.

So increase the guest RAM size to 2GB and while you are at it, remove the DVD drive from the IDE controller and attach it to the SATA controller.

[Panos Kavalagios]

I confirm that the issue was the 1GB RAM. I have increased it to 2GB and the issue was resolved, even with the DVD drive to IDE interface.

The IDE controller for the DVD drive was selected by default in the VM creation screen. Maybe an improvement to create it with SATA default can also be considered.

Thank you very much. You may close the ticket.

[Frank Mehnert]

Thanks for the information.