performance question

   I have a QA and PROD server and has loaded identical Oracle DB 10 i.

   This query runs fast on (10 Minutes) QA and slow on (3 hours) PROD.
    The servers are Red hat Linux.

  INSERT INTO xyz_ime_candidate

                  (proj_key, xref_item_key, xyz_prod_key, match_type,
                   match_score)
         SELECT pn_proj_key, x.xref_item_key, m.xyz_prod_key, 'V',
400
           FROM xyz_ime_xref_data x, xyz_ime_gfy_data1 m
          WHERE x.proj_key = pn_proj_key --and m.proj_key =
pn_proj_key
            AND x.gfy_supp_key = m.gfy_supp_key
            AND x.part_no = m.part_no;

  Both machines performance load are OK, production server load is a little high.
  What could possibly cause this performance difference?   Any hints? Thanks Received on Wed Nov 12 2008 - 13:42:32 CST