Abu Salama ibn 'Abd ar-Rahman asked 'A’isha (may Allah the Exalted be well pleased with her):

“How was the ritual prayer of Allah’s Messenger (ﷺ) during Ramadan?” so she said: “Neither in Ramadan nor in any other month would Allah’s Messenger (ﷺ) add to the total of eleven cycles of [nighttime] ritual prayer. He would perform four — do not ask about their excellence or their length — then he would perform four — do not ask about their excellence or their length — and then he would perform three.” ‘A'isha said (may Allah the Exalted be well pleased with her): “I said: ‘O Messenger of Allah, do you sleep before you perform the odd-numbered ritual prayer [witr]?' He said: ‘O 'A'isha, my eyes may sleep, but my heart does not sleep!’”

حَدَّثَنَا إِسْحَاقُ بْنُ مُوسَى، قَالَ‏:‏ حَدَّثَنَا مَعْنٌ، قَالَ‏:‏ حَدَّثَنَا مَالِكٌ، عَنْ سَعِيدِ بْنِ أَبِي سَعِيدٍ الْمَقْبُرِيِّ، عَنْ أَبِي سَلَمَةَ بْنِ عَبْدِ الرَّحْمَنِ، أَنَّهُ أَخْبَرَهُ أَنَّهُ سَأَلَ عَائِشَةَ، كَيْفَ كَانَتْ صَلاةُ رَسُولِ اللهِ صلى الله عليه وسلم فِي رَمَضَانَ‏؟‏ فَقَالَتْ‏:‏ مَا كَانَ رَسُولُ اللهِ صلى الله عليه وسلم لِيَزِيدَ فِي رَمَضَانَ وَلا فِي غَيْرِهِ عَلَى إِحْدَى عَشْرَةَ رَكْعَةً، يُصَلِّي أَرْبَعًا، لا تَسْأَلْ عَنْ حُسْنِهِنَّ، وَطُولِهِنَّ، ثُمَّ يُصَلِّي أَرْبَعًا لا تَسْأَلْ عَنْ حُسْنِهِنَّ وَطُولِهِنَّ، ثُمَّ يُصَلِّي ثَلاثًا، قَالَتْ عَائِشَةُ‏:‏ قُلْتُ‏:‏ يَا رَسُولَ اللهِ، أَتَنَامُ قَبْلَ أَنْ تُوتِرَ‏؟‏ فَقَالَ‏:‏ يَا عَائِشَةُ، إِنَّ عَيْنَيَّ تَنَامَانِ، وَلا يَنَامُ قَلْبِي‏.‏