The Messenger of Allah ﷺ did not observe either in Ramadan or in other months more than eleven rak'ahs (of the night prayer). He (in the first instance) observed four rak'ahs. Ask not about their excellence and their length (i. e. these were matchless in perfection and length). He again observed four rak'ahs, and ask not about their excellence and their length. He would then observe three rak'ahs (of the Witr prayer). 'A'isha again said: I said: Messenger of Allah, do you sleep before observing the Witr prayer? He said: O 'A'isha, my eyes sleep but my heart does not sleep. (Using translation from Muslim 738a)
أَخْبَرَهُ قَالَ سَأَلْتُ عَائِشَةَ كَيْفَ كَانَتْ صَلَاةُ رَسُولِ اللهِ ﷺ فِي رَمَضَانَ؟ فَقَالَتْ مَا كَانَ يَزِيدُ فِي رَمَضَانَ وَلَا فِي غَيْرِهِ عَلَى إِحْدَى عَشْرَةَ رَكْعَةً يُصَلِّي أَرْبَعًا فَلَا تَسْأَلْ عَنْ طُولِهِنَّ وَحُسْنِهِنَّ ثُمَّ يُصَلِّي أَرْبَعًا فَلَا تَسْأَلْ عَنْ حُسْنِهِنَّ وَطُولِهِنَّ ثُمَّ يُصَلِّي ثَلَاثًا فَقَالَتْ عَائِشَةُ قُلْتُ يَا رَسُولَ اللهِ أَتَنَامُ قَبْلَ أَنْ تُوتِرَ؟ قَالَ يَا عَائِشَةُ إِنَّ عَيْنِي تَنَامُ وَلَا يَنَامُ قَلْبِي