Jami` at-Tirmidhi 2467

Aishah said :" The Messenger of Allah(s.a.w) died and we had a Shatr of barley. We ate from it as Allah willed, then I said to the slave girl: 'Measure it' so she measured it, and it was not long before it was gone." She said: "If we had left it alone then we could have eaten from it more than that." [Her saying]: "Shatr" means a small quantity of barley