Thanks, I forgot about the bugs in 8i x$... If hit ratios were paradise then this would be the fastest db in the land(almost). The application vendor finally certified on 9.2.0.X so I get to drag this database up to only two years behind.;-0 ...JIM... >>> Mladen Gogala <mgogala@xxxxxxxxxxxxxxxxxxxx> 3/14/05 3:24:14 PM >>> James Howerton wrote: >DBA's, > >Has anyone seen library cache hit ratio > 100% ??? This is a very busy >production database, it is usually < 97 % ( I don't tune by hit ratios >I'm just curious). > > >SQL> select SUM(PINS)/(SUM(PINS)+SUM(RELOADS))*100 > from v$librarycache; > > >Library Hit Ratio >-------------------------- > 100.009799 > >1 row selected. > > > This is a well known bug from 8i: all quantities in X$ tables are 32-bit and when the database is busy enough, those quantities can turn negative. That is how you get negative reloads. That was limiting usefulness of statspack on 8i, too.Don't worry, be happy, you're living in the database tuner's paradise: BCHR>100%. What else can you ask for? -- Mladen Gogala Oracle DBA Ext. 121 -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l