ComputingConfidence

Show where the files are stored:

SELECT name, setting
	FROM pg_settings
	WHERE category = 'File Locations';

Listing of memory setting:

SELECT name, setting, unit, category
FROM pg_settings
WHERE name like '%mem%' or name LIKE 'constraint%' or name like '%buffer%'
ORDER BY name;

Alternatively in this way:

SELECT name, setting, current_setting(name),unit, category 
FROM pg_settings 
WHERE name like '%mem%' or name LIKE 'constraint%' or name like '%buffer%' or name like 'effective%' 
ORDER BY name;

Categories and setting:

SELECT DISTINCT category
FROM pg_settings
ORDER BY category;