Which packages to pin

Oracle 8.1.7.4 - Aix 5.2.

As a cure for the ORA-4031 errors which we are getting (up to 5 per day), I am looking at the possibility of pinning some of my stored procedures and triggers. Looking at the Toad Pinned Code screen combined with what I know about the application gives me a good idea of what parts of the application code should be pinned, but I do have some questions:

1. Are triggers normally candidates for pinning? (Toad lists them on its screen, so I infer that they are.)
2. Should I also pin some of the system packages which are displayed on the Toad Pinned Code screen? (e.g. DBMS_OUTPUT, STANDARD, DBMS_STANDARD, DBMS_SQL...)
3. Which of the dynamic views (V$... ) lists the packages, stored procedures, and triggers currently in the shared pool?

Thanks,
Peter Schauss

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