Capture slow in Exadata remote Capture on ASM (4369120)

Capture slow in Exadata remote Capture on ASM

Capture is up to 30 minutes behind in reading from redo logs in a remote Exadata ASM environment.

There is a large number of disks in the redo log disk group and Capture has an insufficient number of threads to cater to this, causing it to be slow reading the redo logs.

Determine the number of disks in the redo disk group and set the SP_OCT_ASM_MULTI_OCI parameter to a relevant value.

This parameter controls the number of threads that Capture uses to read the redo logs.
To use this parameter, you must also set SP_OCT_OLOG_USE_OCI to 1.
The value for this parameter must be set to at least 2 but no more than the number of disks in the redo log disk group.
A large number of threads is not required, and performance actually diminishes with too many threads.
The more threads, the more memory Capture requires.
Start with a small number of threads and monitor performance, then add threads if needed until you obtain an ideal balance between performance gain and memory usage.

Default: 0 (single threaded capture)
Range of valid values: Minimum value is 2, maximum value is the number of disks in the ASM disk group that stores the redo logs. Takes effect: upon restart of the Capture process