2 informix instance on same server

I have 2 informix instance (IDS 9.30 UC3 & IDS 9.40 UC 2) MY QUERY IS THE BUFWAITS VALUE OF THE FIRST INSTANCE IS VERY HIGH AS COMPARED TO THE SECOND INSTANCE. DOES THIS PROBLEM WILL BE RECITIFED BY INCREASING THE LOGFILES VALUE IN ONCONFIG , OR DO I NEED TO LOOK OUT FOR SOMEOTHER PARAMETER attaching the onstat -p output of IDS 9.30 UC3Profile dskreads pagreads bufreads %cached dskwrits pagwrits bufwrits %cached 2383589 18542774 2115624270 99.89 3564883 7238757 142643416 97.50 isamtot open start read write rewrite delete commit rollbk 701330379 13804059 927313924 2721192041 56891192 145860 218928 320584 10285 gp_read gp_write gp_rewrt gp_del gp_alloc gp_free gp_curs 0 0 0 0 0 0 0 ovlock ovuserthread ovbuff usercpu syscpu numckpts flushes 0 0 0 4675341.29 8666.79 6111 18329 bufwaits lokwaits lockreqs deadlks dltouts ckpwaits compress seqscans 7985532 140951 3969872588 2 0 5008 1951805 408539429 ixda-RA idx-RA da-RA RA-pgsused lchwaits 7505 31 327973 334817 1086830254 attaching the onstat -p output of IDS 9.40 UC2 Profile Profile dskreads pagreads bufreads %cached dskwrits pagwrits bufwrits %cached 153123 3454129 36510246 99.58 498711 4130867 5849470 91.47 isamtot open start read write rewrite delete commit rollbk 37625909 3390406 1784744 7920831 1597085 0 0 1529542 0 gp_read gp_write gp_rewrt gp_del gp_alloc gp_free gp_curs 2 0 0 0 0 0 2 ovlock ovuserthread ovbuff usercpu syscpu numckpts flushes 0 0 0 1371.89 283.18 4657 12227 bufwaits lokwaits lockreqs deadlks dltouts ckpwaits compress seqscans 646 137 22408107 0 0 35 41635 43 ixda-RA idx-RA da-RA RA-pgsused lchwaits 1069 280 0 1349 24831