You may have something continuously writing to disk. Are you logging a lot of data to the console? On images before v0.5, the system log is written to disk and may fill up the disk (although I'd expect it to be logrotated). In order to prevent this, run:
systemctl disable rsyslog
systemctl disable syslog.socket
and create file etc/systemd/journald.conf.d/10-volatile.conf with this content:
[Journal]
Storage=volatile
Compress=no
RuntimeMaxUse=16M
Also, use du -sh /root/Bela/projects/* to identify if you have big folders among your projects.
Once you've identified and removed the cause for your disk filling up, consider resizing your filesystem to fill up the whole space available on the SD card (we ship with 16 GB SD cards, but the filesystem is limited to 4 GB to keep compatibility with the space available on the BBB's eMMC): https://learn.bela.io/using-bela/bela-techniques/managing-your-sd-card/#resizing-filesystems-on-an-existing-sd-card
quintosardo Is an application that periodically overwrites 100 very small files (e.g. 100 bytes) on SD card reliable?
It should be, as long as you are smart about the way you are writing the files. Plain overwriting may leave you with corrupted files if the system is powered off while a file is being written. The following approach is much safer:
- write the new file in a temporary location on the same filesystem
- fsync the new file
- move the original file to a backup location on the same filesystem
- fsync the backup file
- move the new file in place of the original file
- fsync the original file
- remove the backup file
On startup, your system should then check for existence and integrity of the original file, failing that look for the backup file and restore it.
To minimise wearing of the SD card and possible failure points, you should limit the writing as much as possible (e.g.: do not write if the file hasn't changed) and also increase the filesystem size as linked above.
