ESP32 Forum

I'm working on a project by using ESP32.
Although the spec say ESP32 has 520kB sram (or 416kB), but most of the sram was used by the basic function running in sram (IRAM_ATTR).I think the free sram is around 100kB

I want o know how to reduce to sram required by the basic function such as BT/Encryption? because I don't need them in the project.

By the way,
because external sram is using the same interface type(QSPI) as external flash,
I think the external sram may not have enough speed as internal memory,
and will impact the performance of ESP32.

disable the bluetooth stack in sdkconfig
I believe bt reserves 64k of mem and adds another 28k when you initialize it.

The memory is divided into 5 parts, you should have a look at the documentation.
I also was advised to look at heap_alloc_caps.c it gives a good view of what memory is where and what is disabled and why.

Goodluck =)