A method of video encoding includes, prior to encoding a first tile of s plurality of tiles of a current picture, initializing a shared row buffer that is shared among multiple processor threads associated with the first tile. The method also includes encoding a first unit of a plurality of units in a first row of the first tile by a first processor thread and using a corresponding first HMVP buffer. The method also includes, when all of the plurality of blocks in the first unit have been encoded, copying contents of the first HMVP buffer into the shared row buffer, copying contents of the shared row buffer into a second HMVP buffer, starting encoding of a unit in a second row of the plurality of rows by the second processor thread using the second HMVP buffer, and resetting the first HMVP buffer.