Read-only file system - /var/lib/openhab/persistence

Setup, Configuration and Use Beginners
1

Hi all,

I am running OH 3.2.0 on my Pi4. I have ~300 Items, most of them are “OpenWeatherMap” Items.
In the openhab.log I see an error: “[ERROR] [d4j.internal.RRD4jPersistenceService] - Could not create rrd4j database file ‘/var/lib/openhab/persistence/rrd4j/OneCallAPIweatherandforecast_ForecastHours09_Apparenttemperature.rrd’: /var/lib/openhab/persistence/rrd4j/OneCallAPIweatherandforecast_ForecastHours09_Apparenttemperature.rrd: Read-only file system”

df -h is showing 100% Usage for zram filesystem

Filesystem      Size  Used Avail Use% Mounted on
/dev/root        29G  5.5G   23G  20% /
devtmpfs        1.9G     0  1.9G   0% /dev
tmpfs           1.9G     0  1.9G   0% /dev/shm
tmpfs           778M  704K  778M   1% /run
tmpfs           5.0M  8.0K  5.0M   1% /run/lock
/dev/mmcblk0p1  253M   49M  204M  20% /boot
/dev/zram1      323M  298M  812K 100% /opt/zram/zram1
overlay1        323M  298M  812K 100% /var/lib/openhab/persistence
/dev/zram2      420M   69M  320M  18% /opt/zram/zram2
overlay2        420M   69M  320M  18% /var/log
tmpfs           389M     0  389M   0% /run/user/1000

zramctl shows

NAME       ALGORITHM DISKSIZE   DATA COMPR TOTAL STREAMS MOUNTPOINT
/dev/zram2 zstd          450M  85.1M  9.1M 30.1M       4 /opt/zram/zram2
/dev/zram1 zstd          350M 300.9M  3.4M  150M       4 /opt/zram/zram1
/dev/zram0 lzo-rle       450M     4K   86B    4K       4 [SWAP]

Is there something I can do? when I restart my system, some space is free again but its running out of space again.

2

Enlarge disk_size in /etc/ztab for the persistence file system and restart.
Assuming your Pi4 has 2GB or more, you can also increase mem_size.

3

Yes it is the 4GB version.
Is there a recommendation for disk_size and mem_size?

4

It’s under discussion. With 4GB you can quadruple the values.