Arduino-esp32: Increasing BLE sketch size of ~156k after adding BluetoothSerial lib

[reaper7]

Hardware:

Board: ESP32 Dev Module
Core Installation/update date: Branch_b4b9a79 05/03/2018
IDE name: Arduino IDE
Flash Frequency: 80Mhz
Upload Speed: 921600

Description:

after adding the BluetoothSerial library (https://github.com/espressif/arduino-esp32/commit/b4b9a79eead317d899fe4f199b4d536b99c25112), sketches which use BLE library (https://github.com/nkolban/ESP32_BLE_Arduino/tree/6bad7b42a96f0aa493323ef4821a8efb0e8815f2) increase finally size by ~156 kbytes!

Lets try for example library: BLE -> example: BLE_uart:

• branch with previous commit (https://github.com/espressif/arduino-esp32/commit/835268c326e0a6c95a36e66f5b6a6d24c2c51f8f) finally sketch size: 931869 bytes (71%)

• branch with BluetoothSerial library (https://github.com/espressif/arduino-esp32/commit/b4b9a79eead317d899fe4f199b4d536b99c25112) finally sketch size: 1088621 bytes (83%)

For this reason my sketches with BLE and several additions do not fit esp32 flash any more,
even though I do not use new BluetoothSerial library in these cases (increase size from 1265006 to 1422022)

What is interesting, I did not notice the increase final sketch size when BLE library is not used.

In the current situation, creation a little more advanced programs with BLE and for e.g. display, becomes impossible due to lack of space.

Sketch:

library: BLE -> example: BLE_uart

[beegee-tokyo]

The Bluetooth stack is very large. You need to change you partition sizes as shown in the Wiki.

[reaper7]

@beegee-tokyo - tnx! this is a option but...
...it's looks like these two libraries use two separate bluetooth stacks?

[beegee-tokyo]

I do not know if there are two different stacks for BLE and Bluetooth, because that is somewhere down below in the ESP-IDF. But I started with using BLE only first and added Bluetooth Serial later (check my blog) the program size didn't double, so I guess there is only one stack.

[reaper7]

In that case, if only one stack, who eats ~157k ? new libbt.a from sdk?

I check this on raw example from library BLE->BLE_Server as-is (without any addition like SerialBT)
current master branch and earlier branch from 5 march 2018 "Add BluetoothSerial library" https://github.com/espressif/arduino-esp32/commit/b4b9a79eead317d899fe4f199b4d536b99c25112
generate output files with ~1085890bytes
while the previous branches (until 4 march 2018) generate output files with ~929130bytes

in my opinion it is a very large increase
but if this is not a bug, then only way is a increase partition size for app

BTW. @beegee-tokyo, great blog, very useful

[jjoe64]

Hi all, I faced the same issue and did not found a easy solution, so I finally forked the library and create a "light version" of it.
Only the BLE server will work. This is a fork of the official esp32 ble library and is stripped to decrease the size. It is only possible to use the ble server features.

I saved about ~30KB program size with this version.

https://github.com/jjoe64/esp32_ble_light

[JoanMCD]

You can save ~10k by remove the long Mode / Vendor / ... String lists in the BThelp.c (or move it to a seperate .c Files)

Also you can save ~47kb (Wow!) of ram by release the classic BT ram if not needed.

Or use the idf direct and save a lot RAM/ROM, have less bugs but also less comfort.

[aravindara]

when i do that my program is compiling with errors

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale[bot]]

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