How do I read my .map file?

Question

I am trying to free up some RAM on my nRF because I am getting Fatal error 0x4, NRF_ERROR_NO_MEM when I try to increase the size of a 2D array. 
 I do not understand how to read my map file. This is the file that contains all my symbols, correct? I sorted all the symbols by size and this is what I get: 
 Apparently all the ".debug_str" take up 11 MB total? That's a lot but if it's all in flash then I don't care. I want to free up RAM. How do I list only the RAM symbols? Do I just delete the entire ".text" section from the .map file?

I filtered out all the ".debug" symbols and I'm left with this: 
 First of all, what is the difference between ".bss.ucHeap" and ."heap"? 
 
 Secondly, I changed my makefile to make the heap size = 0 and my stack size bigger (from 2048 bytes to 3072), but my application STILL Fatal errors with 0x04 when I try to increase the size of a 2D array from [2][75] to [2][140]. I am only using 130 more bytes in the array. Why can't my stack handle it if I just increased its size from 2048 bytes to 3072? I am not using malloc() anywhere. 
 New map file after stack/heap modification:

Andrew Ong · Accepted Answer

I did not know that RAM from 0x20000000-0x20002400 is allocated to the SoftDevice. That would have helped my calculations. 
 I was able to eliminate my NRF_ERR_NO_MEM error by increasing the size of the GATT table by increasing NRF_SDH_BLE_GATTS_ATTR_TAB_SIZE and from 1408 to 3000 and increasing the RAM limits to RAM (rwx) : ORIGIN = 0x20002A38, LENGTH = 0xD5C8. 
 Why do I only get an NRF_ERR_NO_MEM from the char_add() function when I try to increase my array size? My array is allocated with RAM outside of the SoftDevice RAM: address 0x20005f20. Why does an array allocated outside of the SoftDevice RAM affect the Softdevice RAM? 
 How do I know if I have unallocated physical RAM left? Do I just add up everything in the memory addresses0x20002A38-0x20010000 and sum up their sizes + 0x2A38 for the SoftDevice RAM?

How do I read my .map file?

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