ORA-00600 krff_create_fb_log-4

APPLIES TO:

Oracle Server - Enterprise Edition - Version: 10.2.0.3
This problem can occur on any platform.

SYMPTOMS

When attempting to startup a standby database and enable flashback, the following errors are encountered:

ORA-04031: unable to allocate 3981220 bytes of shared memory ("shared pool",
"unknown object","sga heap(1,0)","flashback generation buffer").

ORA-00600: internal error code, arguments: [krff_create_fb_log-4], [], [], [], [], [], [], []

CAUSE

Insufficient memory available for the flashback generation buffer causes the ORA-4031 error.
The ORA-600 [krff_create_fb_log-4] is caused by unpublished Bug 3600284.

When the database start, the RDBMS uses the shared pool to pin many of its objects into memory.

However, with that said, the flashback buffers seem to be outside the shared pool and their size depends
on the '_flashback_generation_buffer_size' parameter. By default this parameter is twice as big as log_buffers.

The cause of the ORA-00600 [krff_create_fb_log-4] problem is due to the first error that failed to
enable flashback, which in this case is the ORA-4031 error.

SOLUTION

To implement the solution, please execute the following steps:

1.  To address the ORA-4031 error, we need to set the parameter "_flashback_generation_buffer_size" to  2MB in either the Pfile or Spfile:

_flashback_generation_buffer_size=2097152

EXAMPLE
========
SQL>alter system set "_flashback_generation_buffer_size"=2097152 scope=SPFILE;

2. To address the ORA-600 [krff_create_fb_log-4] we need to disable and restart the flashback:

a.  shutdown and mount the database

shutdown immediate;
startup mount;
alter database flashback off;
alter database flashback on;
alter database open;