Reverse Offload to DB servers

Arturo Gutierrez

Hi,

Is possible to know the number of times a reverse offload to database servers happen?

Any statistic at cell or database node available?

Thanks

Arturo

Geoff Grandstaff-Oracle

Hi, Arturo.

cellsrvstat (on each individual cell) has a section for 'Reverse Offload related stats'. Ex:

== Reverse Offload related stats ==Number of Remote Nodes                            (I)          0              7Number of Remote Instances                        (I)          0              8Current Cell CPU utilization                      (I)          0              1Number of requests                                (C)          0      31330706Number of requests that were pushed              (C)          0        2085719Average pushback rate for since last stat update  (I)          0              0Average pushback rate for last 200 ms            (I)          0              0Num of reqs not pushed due to low cell cpu        (C)          0      19360302Num of reqs not pushed due to high cell outnet    (C)          0              0Num of reqs not pushed due to high db node innet  (C)          0              0Num rate increase by reverse offload info from db (C)          0          36398Num rate decrease by reverse offload info from db (C)          0        316093Num rate increases from db node cpu information  (C)          0          58745Num rate decreases from db node cpu information  (C)          0          7437Num rate decreases from low cell cpu utilization  (C)          0      552905618Num rate decreases from high cell outnet util    (C)          0              0Num rate decreases from high db node innet util  (C)          0              0

Also, while not a "count", there is also the statistic 'cell physical IO bytes sent directly to DB node to balance CPU'.

https://docs.oracle.com/en/engineered-systems/exadata-database-machine/sagug/exadata-storage-server-monitoring.html#GUID…

Hope this helps.

Regards,

Geoff

Geoff Grandstaff-Oracle

Hi, Arturo.

cellsrvstat (on each individual cell) has a section for 'Reverse Offload related stats'. Ex:

== Reverse Offload related stats ==Number of Remote Nodes                            (I)          0              7Number of Remote Instances                        (I)          0              8Current Cell CPU utilization                      (I)          0              1Number of requests                                (C)          0      31330706Number of requests that were pushed              (C)          0        2085719Average pushback rate for since last stat update  (I)          0              0Average pushback rate for last 200 ms            (I)          0              0Num of reqs not pushed due to low cell cpu        (C)          0      19360302Num of reqs not pushed due to high cell outnet    (C)          0              0Num of reqs not pushed due to high db node innet  (C)          0              0Num rate increase by reverse offload info from db (C)          0          36398Num rate decrease by reverse offload info from db (C)          0        316093Num rate increases from db node cpu information  (C)          0          58745Num rate decreases from db node cpu information  (C)          0          7437Num rate decreases from low cell cpu utilization  (C)          0      552905618Num rate decreases from high cell outnet util    (C)          0              0Num rate decreases from high db node innet util  (C)          0              0

Also, while not a "count", there is also the statistic 'cell physical IO bytes sent directly to DB node to balance CPU'.

https://docs.oracle.com/en/engineered-systems/exadata-database-machine/sagug/exadata-storage-server-monitoring.html#GUID…

Hope this helps.

Regards,

Geoff

Arturo Gutierrez

Hi Geoff,

Thanks for the reply.

I've generated the report with Exawatcher.

I think that this stats are the main:

Num of reqs not pushed due to low cell cpu        (C)           0              0

Num of reqs not pushed due to high cell outnet    (C)           0              0

Num of reqs not pushed due to high db node innet  (C)           0              0

Means, that no reverse offloading is ocurring.

Thanks

Arturo

Geoff Grandstaff-Oracle

Hi, Arturo.

As you probably noticed from the output I posted from cellsrvstat and what you posted with Exawatcher, cellssrvstat is one of the collectors for Exawatcher.

https://docs.oracle.com/en/engineered-systems/exadata-database-machine/sagug/exadata-storage-server-maintaining.html#GUI…

Have a great day.

Regards,

Geoff