Android : Android: reading accelerometer's readings and logging samples in a text file

I want to implement an Android app which has to get accelerometer's sample for long periods, for example 24 hours. Moreover, I want this application to save samples in a text file. I've implemented a service which gets the acceleration samples. It works even when the screen goes off (I write the accelerometer's readings on the pc screen using Log.d()), but when I try to write the samples in a file, sometimes, the sampling, even though it works, it stops before that it should stop. Could it be that there is some limitation to the dimension of the file?