LittleFS stops appending to files

[romix123]

Hi, I have a data logging setup using an ESP-M3 board (but also have test versions on a Wemos D1 mini).
Every hour, I write some small amount of data to a number of files on LittleFS.
The data typically is something like:
['9', 0.49],
or
['11',45433.99],
After a while, sometimes after much more than 24 hours, but typically at 6:00 in the morning, append to file suddenly stops working. I can't figure out what causes this.

void appendFile(const char * path, const char * message) {
File file = LittleFS.open(path, "a");
  if (!file) {…}
if (file.print(message)) {
    debug("Message appended: ");
  } else {
    debugln("Append failed");
  }
  delay(5000);
  file.flush();
  file.close();
}

As you can see, I have incorporated a delay, flush and close file. I even unmount and remount the entire set of log updates. Nothing seems to help. Append simply stops working after a while.
I run esp8266 3.1.1, FS is 128K
Any ideas?

[d-a-v]

You can try and run your code (and LittleFS library) on your computer and see if this bug is reproducible.
On linux, mac or windows/WSL2 with git installation of this core:

$ cd tests/host
$ make help
$ make ../../libraries/LittleFS/examples/SpeedTest/SpeedTest
$ bin32/SpeedTest/SpeedTest
[...]
==> Time to copy 65536 = 65536 bytes = 1 milliseconds = 65.54 MB/s
done
$ make path/to/your/sketch/sketch

[skowron0]

Have you found a solution to this problem? I have the same problem that after some time I can't add anything to the file. Generally the number of bytes used and free space returns null.

[romix123]

NoVerstuurd vanaf mijn iPadOp 10 mrt 2025 om 20:13 heeft skowron0 ***@***.***> het volgende geschreven: Have you found a solution to this problem? I have the same problem that after some time I can't add anything to the file. Generally the number of bytes used and free space returns null. —Reply to this email directly, view it on GitHub, or unsubscribe.You are receiving this because you authored the thread.Message ID: ***@***.***>