ˌoʊˈɛs slˈæʃ θɹˈiːhˈʌndɹɪd sˈɪksti ˈɔːlsoʊ hæd ɐ sˈɪmplɚɹ ˌoʊvɚlˈeɪ sˈɪstəm fɔːɹ tɹˈænsiənt ˌɛsvˌiːsˈiː ɹuːtˈiːnz, jˈuːzɪŋ wˈʌn θˈaʊzənd twˈɛnti fˈoːɹbˈaɪt ˌɛsvˌiːsˈiː tɹˈænsiənt ˈɛɹiəz.
OS/360 also had a simpler overlay system for transient SVC routines, using 1024-byte SVC transient areas.