I am using Oracle 8i(8.1.17) on sun solaris.
After running the database for say 2-3 hours, it becomes slow. My queries takes long time to fetch the results.

If I shutdown the datbase and re-start it, then performance becomes OK.

SGA STATUS AT 30-Dec-2005 04:57:20 PM
Object memory : 35721340 bytes (34.07MB)
Shared sql memory : 23490369 bytes (22.4MB)
Cursors memory : 368500 bytes (.35MB)
Shared pool utilization (total) : 71496251 bytes (68.18MB)
Free memory : 95885068 bytes (91.44MB)
Shared pool allocation (actual) : 131072000 bytes (125MB)
Percentage Utilized : 55%
redo buffer allocation retries : 20
redo log space wait time : 0
Event Total_wait Total Timeout
buffer busy waits : 7839 1582
db file sequential read : 5138 0

I am able to see that free memory is there.

What could be the reason for slowing down.

It would be appreciable to get a resonse.