How did the righteous predecessors, who revived the night with worship, manage their sleep, sustenance, and affairs?

"Performing Qiyam al-Layl (night prayer) throughout the entire year is not legislated, and the Messenger (peace be upon him) disapproved of those who did so, citing the Hadith of the three individuals. He also prevented Abdullah ibn Amr ibn al-Aas from perpetual fasting and prayer. However, it is permissible to revive some nights, as the Prophet (peace be upon him) used to do during the last ten nights of Ramadan. If some of the Salaf (pious predecessors) performed Qiyam al-Layl for the entire night, there is no issue with that if they did not need to work during the day, or if they sufficed with a small amount of sleep."