Al-Ju'ayd bin Abdul Rahman said: Sayyiduna al-Sa'ib bin Yazid (may Allah be pleased with him) said to me: In the time of the Messenger of Allah (peace and blessings be upon him), a sa' was equal to one mudd and a third by your mudd of today; then it was increased in the time of Umar bin Abdul Aziz. The narrator said: And Sayyiduna al-Sa'ib (may Allah be pleased with him) also said: I was taken on Hajj in the time of the Prophet (peace and blessings be upon him) when I was a boy.
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 6651