Exadata Performance Monitoring Part 1

CELLCLI LIST command can be used to monitor and monitor cell performance metrics

To receive some help on specific performance metric, use

list metricdefinition <metric_name> DETAIL

For Example:

CellCLI> list metricdefinition Io_LOAD DETAIL
         name:                   IO_LOAD
         description:            "Average I/O load for hard disks"
         metricType:             Instantaneous
         objectType:             CELL
         unit:                   Number

To display specific metric value, use:

CellCLI> LIST METRICCURRENT CL_CPUT DETAIL
         name:                   CL_CPUT
         alertState:             normal
         collectionTime:         2011-02-17T00:39:32-08:00
         metricObjectName:       cell
         metricType:             Instantaneous
         metricValue:            30.6 %
         objectType:             CELL
LIST command also accepts where clause (attribute filters):

To Show all immediate non-zero performance metric values:

LIST METRICCURRENT where metricValue > 0

CD_IO_TM_R_LG   CD_disk02_cell                                  36,321 us
CD_IO_TM_R_SM   CD_disk01_cell                                  1,347,527 us
CD_IO_TM_R_SM   CD_disk02_cell                                  1,151,048 us
CD_IO_TM_R_SM   CD_disk03_cell                                  931,721 us
CD_IO_TM_R_SM   CD_disk04_cell                                  2,286,866 us
CD_IO_TM_R_SM   CD_disk05_cell                                  958,574 us

To show historical data, use LIST METRICHISTORY Command:

You can use metricobjectname to show specific disk and collectiontime to show specific timeframe.

Make sure to filter data as default "list metrichistory" would provide too much data to comprehend

CellCLI> list metrichistory CD_IO_RQ_W_SM where metricobjectname = CD_disk01_cell and collectiontime > '2011-02-17T00:53:01-08:00' and metricvalue > 0

CD_IO_RQ_W_SM   CD_disk01_cell  350,071 IO requests  2011-02-17T00:53:19-08:00
CD_IO_RQ_W_SM   CD_disk01_cell  356,091 IO requests  2011-02-17T00:54:19-08:00
CD_IO_RQ_W_SM   CD_disk01_cell  358,111 IO requests  2011-02-17T00:55:19-08:00
CD_IO_RQ_W_SM   CD_disk01_cell  381,131 IO requests  2011-02-17T00:56:19-08:00
CD_IO_RQ_W_SM   CD_disk01_cell  454,151 IO requests  2011-02-17T00:57:19-08:00
CD_IO_RQ_W_SM   CD_disk01_cell  470,171 IO requests  2011-02-17T00:58:19-08:00
CD_IO_RQ_W_SM   CD_disk01_cell  640,191 IO requests  2011-02-17T00:59:20-08:00
CD_IO_RQ_W_SM   CD_disk01_cell  850,211 IO requests  2011-02-17T01:00:20-08:00

Great Oracle Internals book

Oracle8i Internal Services for Waits, Latches, Locks, and Memory
Out of number of great "Oracle internals" book this definitely stands out. Ignore 8i - wealth of information in this book deserves it to be read and reread.

I met author in 2001-2002 and he is a shy and very smart DBA from Australia. His website http://www.ixora.com.au/ is a treasure of Oracle internals information and should be studied and used by every reasonable good Oracle DBA.

This Book explain in a great depth internal work of different latches and locks - knowledge which DBA must have to resolve and identify root causes of very complex contentions.