real storage
Computing term for physical main memory, as opposed to virtual storage.
When real storage capacity is insufficient, system performance degrades.
仮想記憶 is virtual storage, an abstraction layer that uses disk space to extend apparent memory, while 実記憶装置 refers to the actual physical RAM.
Compound of 実 (real) + 記憶 (storage/memory) + 装置 (device). A technical term likely coined as a direct translation of the English 'real storage' in computing contexts.