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MMON Consuming a Huge Amount of Memory Raising ORA-4030 and Causing an Instance Hang (Doc ID 1403406.1)

Last updated on FEBRUARY 19, 2019

Applies to:

Oracle Database - Enterprise Edition - Version and later
Information in this document applies to any platform.
***Checked for relevance on 12-Nov-2013***


The MMON process gathers a huge amount of memory while doing an Auto-Flush Slave Action, before raising an ORA-4030 error and hanging the database instance. The instance may need to be restarted in order to solve this problem.

The MMON trace file shows most of the used memory was free but not released, as in:

15 GB total:
14 GB commented, 201 KB permanent
1398 MB free (832 KB in empty extents),
15 GB, 1764740 chunks: "kgh stack " 1395 MB free held




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