Incomplete boot after update

Kutzi

Hi everyone,

a few days ago, I updated my UT 20.04, which is installed on slot b, using ubports-installer. Previously, slot b also had UT 20.04 installed, which I used daily. The update process went smoothly and the operating system ran flawlessly, just as it did before the update.
In the Ubports installer, I saw that two channels with UT 24.04 were already available. A few hours after updating UT 20.04, I decided to switch the slot from b to a and install UT 24.04 there. Previously, slot a had UT 16.04 installed, which was still running, but I was no longer using it. The installation of UT 24.04 in slot a ran without errors and I was able to start the system without any problems. However, after using it for a short time, I noticed that Waydroid would not start. Since I absolutely need Waydroid for a few programs, I switched the slot back from a to b and started UT 20.04 as usual without any errors.
After a while, a message appeared saying that there was insufficient storage space. However, as I did not see this message immediately, it disappeared before I could read the source. UT 20.04 then stopped responding to commands. I could still perform sideways swipe gestures, but I could no longer open apps or press buttons. After a while, a message appeared saying that there was insufficient storage space. However, as I did not see this message immediately, it disappeared before I could read the source. UT 20.04 then stopped responding to commands. I could perform side swipe gestures, but I could no longer open apps or press buttons. Then I had to restart the device, which failed. UT 20.04 would no longer start. After changing the slot from b to a again, UT 24.04 started, but extremely slowly and stopped at the welcome screen. It no longer responded to user input. Reinstallation via ubports-installer is no longer possible for either UT 20.04 or UT 24.04, as the installer aborts shortly before the end of the installation.
I found out the following information using adb-shell:

root@FP3:/ # df
Filesystem            1K-blocks     Used Available Use% Mounted on
tmpfs                   1825940    18616   1807324   2% /
tmpfs                   1825940      804   1825136   1% /dev
tmpfs                   1825940        0   1825940   0% /mnt
tmpfs                   1825940      116   1825824   1% /tmp
tmpfs                   1825940        0   1825940   0% /storage
/dev/block/mmcblk0p62  50044592 50028208     16384 100% /cache

The cache partition appears to be completely full. Could this be the problem?
Can I delete it without losing user data such as contacts, calendar, app settings, etc.?
What do I need to do to delete the cache data?

Thank you very much for your help...

Keneda

@Kutzi
It will not help resolving your problem but I need to say you that "dual booting" UT different versions, even using slots a and b, it not supported.

Because it could lead to problems like the one you encounter.

Above that, I don't know how is managed userspace between slots, but there is slight difference between 20.04 and 24.04 (update from 20 to 24 not recommended), so if user data is shared between slots, it could lead to corruptions.

Luksus

@Kutzi everytime, when you switch from 20.04 to 24.04, after booting, the system creates a backup of your user-config-data.
That's also the reason, why the system feels a bit more slow, directly after the first boot of 24.04.
I am not sure if also backups are created, when switching to 20.04 again.

Have a look at /userdata/backups and clean it up.
Maybe do it from recovery: Boot to recovery, connect through adb, mount -a, and then check user-data backups folder.

Everytime you switch, there will be changes in your /home/phablet/.config and other dot-folders, because there is always something that needs to be migrated e.g. regarding system-apps.
So I won't recommend switching back and forth.