71df82696d
In row mode schema change, it will fail sometime because memory exceeded. When the left memory is enough for sorting but not enough for next block, it will not flush row_block_arr which data in memory and continue to alloc next block so it can't alloc the memory and return directly. And if it can't alloc the memory for block, it need to flush row_block_arr and try it again unless row_block_arr is empty.