Steps to Reproduce

1. run the attached example
2. scroll down to the last row
3. click "Populate Data"

Current Result

it takes 9s to complete the rendering

Expected Result

should take shorter

Debug Information

• if I don't do the step 2, the rendering time is very short

• check

  	_createCellsIfCached: function (dir, size, jump, vr0) {
  ...
  		switch (dir) {
  		case 'south':
  			var tRow = Math.max(cr.bottom + 1, sheet.tp.block ? sheet.tp.block.range.bottom + 1 : 0),
  				lCol = cr.left,
  				rCol = cr.right,
  				bRow = tRow + size - 1,
  				cache = false;
  			bRow = Math.min(bRow, sheet.maxRows - 1);
  			if (ar.containsRange(tRow, lCol, bRow, rCol)) {
  				this.create_(dir, tRow, lCol, bRow, rCol);
  

  this.create_() creates 1919 rows and 20 columns which is much larger than expected. it created all the missing rows from initial-rendered row to the last row. It should render 80 rows (preload row size is 80) from the last row.