Groups chunks together as an array of the specified size. When required to flush, it will queue anything left over.
--a----b------c------d------e--|chunks(2)-------[a,b]---------[c,d]--[e]- Copy
--a----b------c------d------e--|chunks(2)-------[a,b]---------[c,d]--[e]-
Groups chunks together as an array of the specified size. When required to flush, it will queue anything left over.