1. Does that mean that any malloc() could possibly consume RTC memory?This config option allows to add RTC fast memory region to system heap with capability similar to that of DRAM region but without DMA. This memory will be consumed first per heap initialization order by early startup services and scheduler related code. Speed wise RTC fast memory operates on APB clock and hence does not have much performance impact.
2. If no, does memory manger store everything related to RTC heap in RTC memory to make it persist through deep sleep?