dɪvˈaɪsᵻz ðæt duːnˌɑːt səpˈoːɹt mˈɛmɚɹi ɐdɹˈɛsᵻz lˈɔŋ ɪnˈʌf tʊ ɐdɹˈɛs ðɪ ɛntˈaɪɚ fˈɪzɪkəl mˈɛmɚɹi kæn stˈɪl ɐdɹˈɛs ðɪ ɛntˈaɪɚ mˈɛmɚɹi θɹuː ðɪ ˈaɪəmˌuː, ɐvˈɔɪdɪŋ ˌoʊvɚhˈɛdz ɐsˈoʊsɪˌeɪɾᵻd wɪð kˈɑːpɪɪŋ bˈʌfɚz tʊ ænd fɹʌmðə pɚɹˈɪfɚɹəlz ɐdɹˈɛsəbəl mˈɛmɚɹi spˈeɪs.
Devices that do not support memory addresses long enough to address the entire physical memory can still address the entire memory through the IOMMU, avoiding overheads associated with copying buffers to and from the peripheral's addressable memory space.