Setup Guide: Raspberry Pi | Upgrade Problems

Upgrading a Raspberry Pi to a new OS version can sometimes cause problems due to the Pi’s limited SD card storage size. Here are some solutions.

After upgrading from Raspbian wheezy to Raspbian jessie, the system ran very slowly. Just logging in took a long time, command execution was sluggish, and after a few minutes the file system filled up and things stopped working. It turns out that the upgrade changed the size of the swap file to a size that was much too large for the SD card. The fix was to edit the file /etc/dphys-swapfile (e.g. with ‘sudo nano /etc/dphys-swapfile’), changing its last line from

#CONF-MAXSWAP=2048

to

CONF-MAXSWAP=100

That changed the swap file size from unlimited (because the line was originally commented out) to 100 MB.
After that change and a reboot, the system stabilized and ran at its normal speed.

After upgrading and fixing the Slowness problem above, the root filesystem was still fairly full – ‘df .’ reported 77% full. The fix was:

$ sudo apt-get clean
$ df .
Filesystem     1K-blocks    Used Available Use% Mounted on
/dev/root        6581636 3593648   2630612  58% /

That removed some files in /var/cache/apt that were used during the upgrade but are no longer needed.