Asp.net Grid view Fill Bulk Data in background and show some records only without using paging

protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            bindgrid();
            ViewState["currentPage"] = 1;
        }
    }

 public void bindgrid()
    {
        SqlDataAdapter da = new SqlDataAdapter("select * from emp1", cn);
        DataTable dt = new DataTable();
        da.Fill(dt);
        GridView2.DataSource = dt;
        GridView2.DataBind();
        Session["dtEmp"] = dt;
    }

 protected void btnNxt_Click(object sender, EventArgs ev)
    {
        DataTable dtEmp = (DataTable)Session["dtEmp"];

        DataView dvEmp = new DataView(dtEmp);
        int currentPage = Convert.ToInt32(ViewState["currentPage"]) + 99;
        dvEmp.RowFilter = "empNo > " + currentPage;
        GridView2.DataSource = dvEmp;
        GridView2.DataBind();
        ViewState["currentPage"] = currentPage + 1;
 
    }