Arduino ESP32 core 3.3.8 shows ~55kB less available internal RAM comparing to 3.3.7
Posted: Fri Apr 24, 2026 12:15 pm
Arduino ESP32 core 3.3.8 shows ~55kB less available internal RAM comparing to 3.3.7
For my project (audio) it is critical to fit as much data as possible into the fast DRAM, while PSRAM is still available.
The same code for ESP32S3 shows:
3.3.7 : Internal RAM free: 259984 bytes (largest block: 204788)
3.3.8 : Internal RAM free: 204888 bytes (largest block: 188404)
You can see that it is a more than 20% free DRAM drop.
So I wonder, is there any information on this situation? Is it forever, and can only get worse, or is it temporarily not-optimized new features like USB audio card? Or can it be resolved right now with some magic?
Surely I can revert to 3.3.7 (which I did) , but I also wait for the fixes and new features...
Code: Select all
uint32_t dram_free = heap_caps_get_free_size(MALLOC_CAP_INTERNAL);
uint32_t dram_largest = heap_caps_get_largest_free_block(MALLOC_CAP_INTERNAL);
The same code for ESP32S3 shows:
3.3.7 : Internal RAM free: 259984 bytes (largest block: 204788)
3.3.8 : Internal RAM free: 204888 bytes (largest block: 188404)
You can see that it is a more than 20% free DRAM drop.
So I wonder, is there any information on this situation? Is it forever, and can only get worse, or is it temporarily not-optimized new features like USB audio card? Or can it be resolved right now with some magic?
Surely I can revert to 3.3.7 (which I did) , but I also wait for the fixes and new features...