iPad javascript engine ? table rendering flicker

I experience a "flicker开发者_JS百科" (not instant rendering/update) when using simple replaceChild in a table update on the iPad.

Table contains at most 100 rows but this behavior starts at 35 rows on the (iPad 1)

code simplified

tbl = document.getElementById('table1');
tbl_fragment = document.createDocumentFragment(); // contains the rows and cells

tbody = document.createElement("tbody");        
tbody.appendChild(tbl_fragment);

old_tbody = tbl.tBodies[0];

tbl.replaceChild(tbody, old_tbody);