12c: KGLH0 process is causing Shared Pool ORA-04031 errors and latch contention

Are you looking to upgrade your Oracle database to 12.1.0.2 soon?  You might want to read "Bug 20370037 - Shared Pool from KGLH0 constantly growing causing ORA-04031 and Latch contention" from MOS note 2119923.1 because there seems to be several well known bugs with the KGLH0 process and this document has steps for different ways to mitigate this.  What does that mean?  If there are a lot of ways to encounter this in the system, then you need to prepare for encountering it so deploy the upgrade in QA and stress test to see if you run into this!!

11gR2 database bug due to ASM defaults

Did you know that ORA-04031 errors can crop up on you, if you have ASM configured with the default memory parameters being too low?  Serious!  Look up MOS Note ID 14292825.8 where a patch is suggested AND an alternative to patching by setting your MEMORY_TARGET value correctly.  You may want to proactively verify that your databases on 11.2.0.3 and up (not including 12.1) have the correct ASM values set to avoid unexpected outages!