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Exadata smart scans usage or not?

LauryOct 22 2014 — edited Oct 29 2014

Hi,


I have an Oracle 11gR2 EE database on Exadata.
I have two concurrent bulk-insert processes.

In Top Waits I have significant waits for:
1) "read by other session",
2) "latch free"
3) "cell single block physical read"


1) and 2) I can explain it by the fact that there is a where clause with multi-columns for both queries,
and that both queries access the same table.

The full scans are offloaded to the Exadata storage, as I also have a wait event for "cell multiblock physical read".
But are the "smart scans" used?

How can I explain the "cell single block physical read"? The execution plans do not show any index use.

I also have:

SQL> select name, value from v$spparameter where name = 'cell_offload_processing';

Parameter                                Value
---------------------------------------- ----------------------------------------
cell_offload_processing

SQL> show parameter db_name

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_name                              string      OHIBO11A

SQL> select name, value from v$parameter where name = 'cell_offload_processing';

Parameter                                Value
---------------------------------------- ----------------------------------------
cell_offload_processing                  TRUE


Thanks by advance for any indication if you have.
Kind Regards.

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Locked on Nov 26 2014
Added on Oct 22 2014
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