Once I was contacted with quite interesting problem.
From the user’s side problem was that after some time of properly working system started to return ORA-04031 even on simple queries like: SELECT * FROM dual;
The main part of Shared Pool was subpool named “qksbgCreateSessionEnv:qks“.
The most interesting fact was that this subpool was increasing by 200 bytes every second until no more free memory in Shared Pool.
Searching on site My Oracle Support I found the source of this situation:
BUG:5548510 _FIX_CONTROL parameter leaks memory in the shared pool
which is fixed in: 10.2.0.4, 126.96.36.199
- keep your system on latest available patchset for your release
- install latest available cumulative bundle over your patchset, or PSU for unix/linux platforms
- regularly look through know issues for your version