Simulating small buffer sizes on Android emulator


I’ve recently tracked down an audio bug reported on an Android app, which was working fine, until I updated the Android SDK to 27 (think it was 25 before). There were some other changes, but the audio code has not been touched in quite a while, so it was a surprise when I got reports that certain devices (Samsung S7 running Android 8 and Pixel running Android 9) were behaving differently.

Once I managed to get hold of one of the offending devices, I found that (as suspected) the issue was due to some new low buffer sizes. Beforehand and on other devices I was getting buffer sizes of 4800, and now, at least on the Samsung, I am seeing 240. The code I wrote was based on the assumption that I was getting large buffer sizes :slight_smile:

Since the device in question belongs to my client, and I had to give it back before completing the fix, does anyone know if it’s at all possible to simulate low buffer sizes in the Android emulator? :iphone:



The device’s buffer size has always been device dependent. A buffer size of 240 frames, whilst on the low side, isn’t the lowest (Pixel devices usually have 192 frames and Nexus 9 has 128 frames). You shouldn’t make the assumption that it is fixed or above a certain size.

The “new low buffer size” is almost certainly because your app is (for some reason) now obtaining a low latency stream. These have lower buffer sizes for reduced latency.

If latency isn’t an issue you could just increase the buffer size to a large (say 20) multiple of the native buffer size (which can be obtained using

I’m afraid not. Or at least not without generating your own emulator image. You’re probably better off getting a real Android device for testing since the emulator doesn’t accurately simulate CPU bandwidth either. Pixel 1 has a native buffer size of 192, runs Android Q and shouldn’t break the bank as it’s a few years old now.



Thanks Don, I was hoping you’d chime in here :slight_smile:

Ok, both good tips. I’ll grab a Pixel on eBay. Cheers!