decalre
    vn_cnt pls_integer;
  begin
    insert /*+append */ into gt_performance(c1,c2) select c1,c2 from t_performance@remotedb;
    commit;
    insert into t_performance(c1,c2) select .... from gt_performance where ... group ...;
    vn_cnt:=sql%rowcount;
    dbms_output.put_line(vn_cnt);
    commit;
  

  decalre
    vn_cnt pls_integer;
  begin
    insert /*00+append */ into gt_performance(c1,c2) select c1,c2 from t_performance@remotedb;   --disable append
    --commit;  --disable commit
    insert into t_performance(c1,c2) select .... from gt_performance where ... group ...;
    vn_cnt:=sql%rowcount;
    dbms_output.put_line(vn_cnt);
    commit;
  

insert into t_performance(c1,c2) select ... from gt_performance@remotedb where ... group ...;