MQTT client from ESP-IDF framework used on ESP32 uses too much RAM

[peterhalicky]

The problem

Pull request 5157 introduced a different MQTT client than what was used before on ESP32. This new client, however, uses nearly 21kB more memory than the one that was in use before (Arduino).

With commit preceding 9980b9972fcac080a1eb1987107484644e7a8d1d, I get this:

[08:00:29][D][debug:072]: Free Heap Size: 53036 bytes

With commit 9980b9972fcac080a1eb1987107484644e7a8d1d, I get this:

[08:03:02][D][debug:072]: Free Heap Size: 32540 bytes

This difference can mean whether a configuration will work just fine, or will be crashing horribly. The PR doesn't say why is the ESP-IDF mqtt client better - so unless there's a very good reason to use ESP-IDF mqtt client, I'd say esphome should switch back to using the Arduino library.

Which version of ESPHome has the issue?

commit 9980b997

What type of installation are you using?

Docker

Which version of Home Assistant has the issue?

No response

What platform are you using?

ESP32

Board

esp32dev

Component causing the issue

mqtt

Example YAML snippet

esphome:
  name: something
  platform: ESP32
  board: esp32dev

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

debug:
  update_interval: 5s

logger:

ota:

mqtt:
  broker: host-name

web_server:
  port: 80

esp32_ble_tracker:

xiaomi_ble:

text_sensor:
  - platform: debug
    device:
      name: "Device Info"
    reset_reason:
      name: "Reset Reason"

sensor:
  - platform: debug
    free:
      name: "Heap Free"
    block:
      name: "Heap Max Block"
    loop_time:
      name: "Loop Time"

  - platform: pvvx_mithermometer
    mac_address: "A4:C1:38:99:20:13"
    temperature:
      name: "AAA Temperature"
    humidity:
      name: "AAA Humidity"
    battery_level:
      name: "AAA Battery level"
    battery_voltage:
      name: "AAA Battery voltage"
  - platform: pvvx_mithermometer
    mac_address: "A4:C1:38:E1:74:A9"
    temperature:
      name: "BBB Temperature"
    humidity:
      name: "BBB Humidity"
    battery_level:
      name: "BBB Battery level"
    battery_voltage:
      name: "BBB Battery voltage"

Anything in the logs that might be useful for us?

No response

Additional information

No response

[github-actions[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.

[spuder]

Correct me if I'm wrong, but can't you switch back to the arduino framework with something like this?

esphome:
  framework: 
    type: arduino

[peterhalicky]

Arduino framework is used by default anyway; that config won't change anything: https://esphome.io/components/esp32.html#esp32-arduino-framework