Thanks a lot for your help - here is the snap - about 10 min long, mj
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STATSPACK report for

DB Name DB Id Instance Inst Num Release RAC Host
------------ ----------- ------------ -------- ----------- --- ----------------
ORAPERF 1029455018 oraperf 1 10.1.0.4.0 NO aixperfdb

Snap Id Snap Time Sessions Curs/Sess Comment
--------- ------------------ -------- --------- -------------------
Begin Snap: 720 11-Jan-06 15:40:54 65 679.0
End Snap: 721 11-Jan-06 15:49:54 65 683.1
Elapsed: 9.00 (mins)

Cache Sizes (end)
~~~~~~~~~~~~~~~~~
Buffer Cache: 5,312M Std Block Size: 4K
Shared Pool Size: 960M Log Buffer: 195,313K

Load Profile
~~~~~~~~~~~~ Per Second Per Transaction
--------------- ---------------
Redo size: 1,562,471.84 36,845.92
Logical reads: 28,916.59 681.91
Block changes: 10,014.51 236.16
Physical reads: 2,762.25 65.14
Physical writes: 1,298.34 30.62
User calls: 7,950.90 187.50
Parses: 702.14 16.56
Hard parses: 0.01 0.00
Sorts: 3.25 0.08
Logons: 0.03 0.00
Executes: 4,119.29 97.14
Transactions: 42.41

% Blocks changed per Read: 34.63 Recursive Call %: 9.94
Rollback per transaction %: 0.00 Rows per Sort: 22.07

Instance Efficiency Percentages (Target 100%)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Buffer Nowait %: 99.95 Redo NoWait %: 100.00
Buffer Hit %: 90.45 In-memory Sort %: 100.00
Library Hit %: 100.01 Soft Parse %: 100.00
Execute to Parse %: 82.95 Latch Hit %: 99.81
Parse CPU to Parse Elapsd %: 92.63 % Non-Parse CPU: 96.82

Shared Pool Statistics Begin End
------ ------
Memory Usage %: 40.08 40.10
% SQL with executions>1: 53.63 53.71
% Memory for SQL w/exec>1: 51.69 51.93

Top 5 Timed Events
~~~~~~~~~~~~~~~~~~ % Total
Event Waits Time (s) Call Time
-------------------------------------------- ------------ ----------- ---------
db file sequential read 1,491,521 15,412 86.02
CPU time 1,079 6.02
db file parallel write 47,953 946 5.28
log file sync 23,929 231 1.29
log file parallel write 43,225 177 .99
-------------------------------------------------------------
Wait Events DB/Inst: ORAPERF/oraperf Snaps: 720-721
-> s - second
-> cs - centisecond - 100th of a second
-> ms - millisecond - 1000th of a second
-> us - microsecond - 1000000th of a second
-> ordered by wait time desc, waits desc (idle events last)

Avg
Total Wait wait Waits
Event Waits Timeouts Time (s) (ms) /txn
---------------------------- ------------ ---------- ---------- ------ --------
db file sequential read 1,491,521 0 15,412 10 65.1
db file parallel write 47,953 0 946 20 2.1
log file sync 23,929 0 231 10 1.0
log file parallel write 43,225 0 177 4 1.9
SQL*Net break/reset to clien 97,200 0 25 0 4.2
control file sequential read 2,323 0 10 4 0.1
class slave wait 2 2 10 4883 0.0
Queue Monitor Task Wait 2 0 10 4883 0.0
control file parallel write 230 0 6 24 0.0
enq: TX - index contention 1,296 0 5 4 0.1
latch: cache buffers chains 1,032 1,028 2 2 0.0
buffer busy waits 7,045 0 1 0 0.3
enq: TX - row lock contentio 1 0 1 1282 0.0
latch free 204 183 1 3 0.0
process startup 8 0 0 53 0.0
latch: library cache 224 0 0 2 0.0
read by other session 52 0 0 6 0.0
control file single write 17 0 0 9 0.0
db file scattered read 22 0 0 4 0.0
rdbms ipc reply 121 0 0 1 0.0
LGWR wait for redo copy 947 0 0 0 0.0
latch: shared pool 35 0 0 1 0.0
latch: library cache pin 27 0 0 1 0.0
SQL*Net more data to client 198 0 0 0 0.0
latch: row cache objects 7 0 0 1 0.0
enq: SQ - contention 4 0 0 1 0.0
latch: redo allocation 5 0 0 1 0.0
enq: HW - contention 4 0 0 1 0.0
latch: In memory undo latch 3 0 0 1 0.0
latch: cache buffers lru cha 3 0 0 0 0.0
buffer deadlock 165 165 0 0 0.0
latch: enqueue hash chains 1 0 0 0 0.0
SQL*Net message from client 2,188,940 0 4,012 2 95.6
queue messages 109 109 532 4883 0.0
virtual circuit status 18 18 527 29297 0.0
Queue Monitor Wait 18 18 527 29297 0.0
wakeup time manager 2 0 527 ###### 0.0
jobq slave wait 173 170 500 2891 0.0
SQL*Net message to client 2,188,933 0 4 0 95.6
SQL*Net more data from clien 5 0 0 17 0.0
-------------------------------------------------------------
Background Wait Events DB/Inst: ORAPERF/oraperf Snaps: 720-721
-> ordered by wait time desc, waits desc (idle events last)

Avg
Total Wait wait Waits
Event Waits Timeouts Time (s) (ms) /txn
---------------------------- ------------ ---------- ---------- ------ --------
db file parallel write 47,954 0 946 20 2.1
log file parallel write 43,225 0 177 4 1.9
Queue Monitor Task Wait 2 0 10 4883 0.0
control file parallel write 234 0 6 24 0.0
control file sequential read 90 0 1 7 0.0
process startup 8 0 0 53 0.0
db file sequential read 98 0 0 2 0.0
control file single write 18 0 0 9 0.0
db file scattered read 17 0 0 5 0.0
rdbms ipc reply 121 0 0 1 0.0
LGWR wait for redo copy 949 0 0 0 0.0
latch: cache buffers chains 4 4 0 5 0.0
latch: redo allocation 4 0 0 0 0.0
latch: cache buffers lru cha 4 0 0 0 0.0
buffer busy waits 2 0 0 0 0.0
rdbms ipc message 23,385 2,612 6,292 269 1.0
smon timer 54 0 635 11762 0.0
Queue Monitor Wait 18 18 527 29297 0.0
-------------------------------------------------------------

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