Hi,
We have a 3 node RAC instance on Linux x86 2.14 boxes using Oracle 9.2.0.7. The boxes have 4 Cpu with 8g mem on each one of them. Below are the important parameter settings

db_cache_size big integer 2147483648
java_pool_size big integer 67108864
large_pool_size big integer 0
hared_pool_size big integer 536870912
session_cached_cursors integer 200


The client is running some performance tests using mercury. They are using Oracle E-business suite. The are expereincing slowness when concurrent users connect and perform some routine tasks. The statspack shows a lot of enqueue waits:

Event Waits Time (s) Ela Time
-------------------------------------------- ------------ ----------- --------
rdbms ipc reply 466 720 27.77
CPU time 719 27.73
enqueue 674,444 294 11.33
global cache null to x 23,541 202 7.80
global cache null to s 7,895 160 6.19
-------------------------------------------------------------
Also a lot of sleeps for ges caches resource list latch

gcs opaque info freelist 93,477 0.0 0.0 0 0
gcs resource freelist 4,262 0.0 0.0 0 0
gcs resource hash 625,158 0.0 0.0 0 269 0.7
gcs resource scan list 540 0.0 0 0
gcs shadows freelist 7,611 0.1 0.0 0 0
ges caches resource list 435,062 0.1 0.0 0 43,539 0.5


I have attached the statspack report too. What can be done in order to tune the RAC instance. Any help is appreciated.

Thanks.