Increase streaming buffer

[garageeks]

Hi to all,
I'm using the library to stream MP3 music from a web radio.
It works beautifully, but when the Wi-Fi connection is so-so, it drops out periodically for a few seconds.
I have left the default configuration in AudioConfig.h, therefore USE_URLSTREAM_TASK should be already disabled.

In this case the Internal Total heap is 307556 bytes, internal Free Heap 109656 bytes, Max Alloc Heap 53236 bytes

I increased the URLStream buffer from the default 1024 to 48000 bytes, however this equals to barely 3 seconds of a 128kbps stream.
URLStream url(wifi, password,48000);

The internal Total heap is 307556 bytes, internal Free Heap 62672 bytes, Max Alloc Heap 48116 bytes.

If I try to increase the buffer to 65536 bytes it crashes at startup.

abort() was called at PC 0x40159787 on core 0


Backtrace:0x4008384d:0x3ffe3a500x4008cffd:0x3ffe3a70 0x400921d9:0x3ffe3a90 0x40159787:0x3ffe3b10 0x401597ce:0x3ffe3b30 0x40159b13:0x3ffe3b50 0x40159a72:0x3ffe3b70 0x40159bad:0x3ffe3b90 0x400d8987:0x3ffe3bb0 0x400d8ca2:0x3ffe3bf0 0x400ed7b7:0x3ffe3c10 0x40082f4e:0x3ffe3c40 0x400792ba:0x3ffe3c90  |<-CORRUPTED

  #0  0x4008384d:0x3ffe3a50 in panic_abort at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/panic.c:402
  #1  0x4008cffd:0x3ffe3a70 in esp_system_abort at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/esp_system.c:128
  #2  0x400921d9:0x3ffe3a90 in abort at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/newlib/abort.c:46
  #3  0x40159787:0x3ffe3b10 in __cxxabiv1::__terminate(void (*)()) at /builds/idf/crosstool-NG/.build/HOST-x86_64-w64-mingw32/xtensa-esp32-elf/src/gcc/libstdc++-v3/libsupc++/eh_terminate.cc:47     
  #4  0x401597ce:0x3ffe3b30 in std::terminate() at /builds/idf/crosstool-NG/.build/HOST-x86_64-w64-mingw32/xtensa-esp32-elf/src/gcc/libstdc++-v3/libsupc++/eh_terminate.cc:57
  #5  0x40159b13:0x3ffe3b50 in __cxa_throw at /builds/idf/crosstool-NG/.build/HOST-x86_64-w64-mingw32/xtensa-esp32-elf/src/gcc/libstdc++-v3/libsupc++/eh_throw.cc:95
  #6  0x40159a72:0x3ffe3b70 in operator new(unsigned int) at /builds/idf/crosstool-NG/.build/HOST-x86_64-w64-mingw32/xtensa-esp32-elf/src/gcc/libstdc++-v3/libsupc++/new_op.cc:54
  #7  0x40159bad:0x3ffe3b90 in operator new[](unsigned int) at /builds/idf/crosstool-NG/.build/HOST-x86_64-w64-mingw32/xtensa-esp32-elf/src/gcc/libstdc++-v3/libsupc++/new_opv.cc:32
  #8  0x400d8987:0x3ffe3bb0 in audio_tools::URLStreamDefault::URLStreamDefault(char const*, char const*, int) at .pio/libdeps/esp32dev/audio-tools/src/AudioHttp/URLStream.h:54
      (inlined by) audio_tools::URLStream::URLStream(char const*, char const*, int) at .pio/libdeps/esp32dev/audio-tools/src/AudioHttp/URLStreamESP32.h:178
  #9  0x400d8ca2:0x3ffe3bf0 in _GLOBAL__sub_I__ZN11audio_tools8mime_pcmE at src/main.cpp:18
      (inlined by) _GLOBAL__sub_I__ZN11audio_tools8mime_pcmE at src/main.cpp:71
  #10 0x400ed7b7:0x3ffe3c10 in do_global_ctors at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/startup.c:185
      (inlined by) start_cpu0_default at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/startup.c:404
  #11 0x40082f4e:0x3ffe3c40 in call_start_cpu0 at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/port/cpu_start.c:648
  #12 0x400792ba:0x3ffe3c90 in ?? ??:0

Is there any chance to increase buffer without resorting to PSRAM?
Maybe by reducing STACK_SIZE 30000? Or leave default buffer size and increase URL_STREAM_BUFFER_COUNT?

[pschatzmann]

This buffer setting is only used to support single byte reads which are not used at all in this case.

Did you try with some other radio stations ? I would recommend to use radio urls w/o ssl since ssl adds a lot of overhead.
Further info can be found in https://github.com/pschatzmann/arduino-audio-tools/wiki/Performance

[garageeks]

Thank you for pointing out I was working with the wrong buffer.
Yep it is a HTTP streaming.
I increased URL_STREAM_BUFFER_COUNT to 64 and it appears to be way more resilient to bad connection quality.