OS statistics don't add up to real elapsed time

I setup the SQL script that follows to show what I think is a bug in Oracle. But it is possible that I also don't understand what these statistics are recording. My understanding is that the OS statistics that record time should total to the actual time spent by the user process. Some of the statistics, such as the CPU ones, seem to work fine. But 'OS User lock wait sleep time', and 'OS All other sleep time' are way out of whack. This is on Solaris 8 with Oracle 9.2.0.5.  I expect the final value of "session_time_after" to be close to the 100 seconds that sqlplus waits on the sleep command, but it is way off on my system.

Thanks for any comments/help.

• Bobby

set termout on
set echo on
spool osstatsproblem.log
alter session set timed_os_statistics=1; drop table before;
create table before as
select sum(value)/100 session_time_before from v$sesstat where sid=(SELECT sid from v$session where audsid=USERENV('SESSIONID'))
and statistic# in
(select statistic# from v$statname where name in ('OS User level CPU time',
'OS System call CPU time',
'OS Other system trap CPU time',
'OS Text page fault sleep time',
'OS Data page fault sleep time',
'OS Kernel page fault sleep time',
'OS User lock wait sleep time',
'OS All other sleep time',
'OS Wait-cpu (latency) time'));

host sleep 100
select session_time_after-session_time_before elapsed_seconds from
before,
(select sum(value)/100 session_time_after from v$sesstat where sid=(SELECT sid from v$session where audsid=USERENV('SESSIONID'))
and statistic# in
(select statistic# from v$statname where name in ('OS User level CPU time',
'OS System call CPU time',
'OS Other system trap CPU time',
'OS Text page fault sleep time',
'OS Data page fault sleep time',
'OS Kernel page fault sleep time',
'OS User lock wait sleep time',
'OS All other sleep time',
'OS Wait-cpu (latency) time')));

drop table before;
spool off Received on Fri Aug 13 2004 - 11:58:28 CDT