Time executing NVS functions

[Jonas A]

Hello,

Is this function non-blocking?

esp_err_t nvs_set_u32(nvs_handle_thandle, const char *key, uint32_t value)

Writing to flash usually takes a few milliseconds. Does this function block the current task x milliseconds? Or is there a background task that write to the flash memory?

BR
Jonas

[ESP_jakob]

Hi Jonas,

the NVS functions are all blocking. There is no background thread going on. Since NVS may re-order data if one page is full, there's a potential erasure of flash which takes a "long" time, blocking the current thread.

If you want to do something during the time of writing, then please use a FreeRTOS task or alternatively std::async, if you're using C++.

Best,
Jakob

[Jonas A]

Thanks for the answer. I measured the time of

esp_err_t nvs_set_u32(nvs_handle_thandle, const char *key, uint32_t value)

and it took 500 uS to execute.