在golang中加载语言JSON文件的最佳方法是什么?

I have json files for language support and each json files around 3 mb but i wondered which way is good for performance, lightweight and fast in golang.

reading from json files fmt.Printf("%s: %d ", lang["tr"].Back)

or

putting all json into a map and read from map

{"tr": { "Back": "geri", "Next": "ileri", "Day": "gün"}}

10 years ago when we worked with old language we had montly 20-30 gb traffic only for reading xml language files. thank you