Exadata storage version 11.2.3.2.1 is the minimum version required to use this write back flash cache option.
Oracle rdbms software 11.2.0.3 BP9 or later is necessary.
If you find in AWR reports “free buffer waits” or high I/O time for write operation ,you should consider using write-back option.
Steps for Enabling Write back flash cache:
First of all,you don’t need the stop CRS or database (This is ROLLING method) ,you can do it cell by cell.
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[root@owtcel01 ~]# dcli -l root -g cell_group "cellcli -e list cell detail" | grep "flashCacheMode" owtcel01: flashCacheMode: WriteThrough owtcel02: flashCacheMode: WriteThrough owtcel03: flashCacheMode: WriteThrough owtcel04: flashCacheMode: WriteThrough owtcel05: flashCacheMode: WriteThrough owtcel06: flashCacheMode: WriteThrough
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</pre> CellCLI> list cell detail name: owtcel04 bbuTempThreshold: 60 bbuChargeThreshold: 800 bmcType: IPMI cellVersion: OSS_11.2.3.2.1_LINUX.X64_130109 cpuCount: 24 diagHistoryDays: 7 fanCount: 8/8 fanStatus: normal flashCacheMode: WriteThrough--------------------------------Current Mode id: 1250FM5062 interconnectCount: 3 interconnect1: bondib0 iormBoost: 0.4 ipaddress1: 192.168.30.8/22 kernelVersion: 2.6.32-400.11.1.el5uek locatorLEDStatus: off makeModel: Oracle Corporation SUN FIRE X4270 M3 SAS metricHistoryDays: 7 offloadEfficiency: 7,323.6 powerCount: 2/2 powerStatus: normal releaseVersion: 11.2.3.2.1 releaseTrackingBug: 14522699 smtpFrom: "Exadata OWT HALF" smtpFromAddr: unixasr@*** smtpServer: *** smtpToAddr: unixasr@*** status: online temperatureReading: 19.0 temperatureStatus: normal upTime: 28 days, 14:34 cellsrvStatus: running msStatus: running rsStatus: running <pre>
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drop flashcache
</pre> CellCLI> drop flashcache Flash cache owtcel03_FLASHCACHE successfully dropped <pre>
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Be sure asmdeactivationoutcome is YES is before disabling grid disk
</pre> CellCLI> list griddisk attributes name,asmmodestatus,asmdeactivationoutcome DATA_OWT_CD_00_owtcel03 ONLINE Yes DATA_OWT_CD_01_owtcel03 ONLINE Yes DATA_OWT_CD_02_owtcel03 ONLINE Yes DATA_OWT_CD_03_owtcel03 ONLINE Yes DATA_OWT_CD_04_owtcel03 ONLINE Yes DATA_OWT_CD_05_owtcel03 ONLINE Yes DATA_OWT_CD_06_owtcel03 ONLINE Yes DATA_OWT_CD_07_owtcel03 ONLINE Yes DATA_OWT_CD_08_owtcel03 ONLINE Yes DATA_OWT_CD_09_owtcel03 ONLINE Yes DATA_OWT_CD_10_owtcel03 ONLINE Yes DATA_OWT_CD_11_owtcel03 ONLINE Yes DBFS_DG_CD_02_owtcel03 ONLINE Yes DBFS_DG_CD_03_owtcel03 ONLINE Yes DBFS_DG_CD_04_owtcel03 ONLINE Yes DBFS_DG_CD_05_owtcel03 ONLINE Yes DBFS_DG_CD_06_owtcel03 ONLINE Yes DBFS_DG_CD_07_owtcel03 ONLINE Yes DBFS_DG_CD_08_owtcel03 ONLINE Yes DBFS_DG_CD_09_owtcel03 ONLINE Yes DBFS_DG_CD_10_owtcel03 ONLINE Yes DBFS_DG_CD_11_owtcel03 ONLINE Yes RECO_OWT_CD_00_owtcel03 ONLINE Yes RECO_OWT_CD_01_owtcel03 ONLINE Yes RECO_OWT_CD_02_owtcel03 ONLINE Yes RECO_OWT_CD_03_owtcel03 ONLINE Yes RECO_OWT_CD_04_owtcel03 ONLINE Yes RECO_OWT_CD_05_owtcel03 ONLINE Yes RECO_OWT_CD_06_owtcel03 ONLINE Yes RECO_OWT_CD_07_owtcel03 ONLINE Yes RECO_OWT_CD_08_owtcel03 ONLINE Yes RECO_OWT_CD_09_owtcel03 ONLINE Yes RECO_OWT_CD_10_owtcel03 ONLINE Yes RECO_OWT_CD_11_owtcel03 ONLINE Yes <pre>
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</pre> CellCLI> alter griddisk all inactive GridDisk DATA_OWT_CD_00_owtcel03 successfully altered GridDisk DATA_OWT_CD_01_owtcel03 successfully altered GridDisk DATA_OWT_CD_02_owtcel03 successfully altered GridDisk DATA_OWT_CD_03_owtcel03 successfully altered GridDisk DATA_OWT_CD_04_owtcel03 successfully altered GridDisk DATA_OWT_CD_05_owtcel03 successfully altered GridDisk DATA_OWT_CD_06_owtcel03 successfully altered GridDisk DATA_OWT_CD_07_owtcel03 successfully altered GridDisk DATA_OWT_CD_08_owtcel03 successfully altered GridDisk DATA_OWT_CD_09_owtcel03 successfully altered GridDisk DATA_OWT_CD_10_owtcel03 successfully altered GridDisk DATA_OWT_CD_11_owtcel03 successfully altered GridDisk DBFS_DG_CD_02_owtcel03 successfully altered GridDisk DBFS_DG_CD_03_owtcel03 successfully altered GridDisk DBFS_DG_CD_04_owtcel03 successfully altered GridDisk DBFS_DG_CD_05_owtcel03 successfully altered GridDisk DBFS_DG_CD_06_owtcel03 successfully altered GridDisk DBFS_DG_CD_07_owtcel03 successfully altered GridDisk DBFS_DG_CD_08_owtcel03 successfully altered GridDisk DBFS_DG_CD_09_owtcel03 successfully altered GridDisk DBFS_DG_CD_10_owtcel03 successfully altered GridDisk DBFS_DG_CD_11_owtcel03 successfully altered GridDisk RECO_OWT_CD_00_owtcel03 successfully altered GridDisk RECO_OWT_CD_01_owtcel03 successfully altered GridDisk RECO_OWT_CD_02_owtcel03 successfully altered GridDisk RECO_OWT_CD_03_owtcel03 successfully altered GridDisk RECO_OWT_CD_04_owtcel03 successfully altered GridDisk RECO_OWT_CD_05_owtcel03 successfully altered GridDisk RECO_OWT_CD_06_owtcel03 successfully altered GridDisk RECO_OWT_CD_07_owtcel03 successfully altered GridDisk RECO_OWT_CD_08_owtcel03 successfully altered GridDisk RECO_OWT_CD_09_owtcel03 successfully altered GridDisk RECO_OWT_CD_10_owtcel03 successfully altered GridDisk RECO_OWT_CD_11_owtcel03 successfully altered <pre>
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</pre> CellCLI> alter cell shutdown services cellsrv Stopping CELLSRV services... The SHUTDOWN of CELLSRV services was successful CellCLI> alter cell flashCacheMode=writeback Cell owtcel03 successfully altered CellCLI> alter cell startup services cellsrv Starting CELLSRV services... The STARTUP of CELLSRV services was successful <pre>
</pre> CellCLI> alter griddisk all active GridDisk DATA_OWT_CD_00_owtcel03 successfully altered GridDisk DATA_OWT_CD_01_owtcel03 successfully altered GridDisk DATA_OWT_CD_02_owtcel03 successfully altered GridDisk DATA_OWT_CD_03_owtcel03 successfully altered GridDisk DATA_OWT_CD_04_owtcel03 successfully altered GridDisk DATA_OWT_CD_05_owtcel03 successfully altered GridDisk DATA_OWT_CD_06_owtcel03 successfully altered GridDisk DATA_OWT_CD_07_owtcel03 successfully altered GridDisk DATA_OWT_CD_08_owtcel03 successfully altered GridDisk DATA_OWT_CD_09_owtcel03 successfully altered GridDisk DATA_OWT_CD_10_owtcel03 successfully altered GridDisk DATA_OWT_CD_11_owtcel03 successfully altered GridDisk DBFS_DG_CD_02_owtcel03 successfully altered GridDisk DBFS_DG_CD_03_owtcel03 successfully altered GridDisk DBFS_DG_CD_04_owtcel03 successfully altered GridDisk DBFS_DG_CD_05_owtcel03 successfully altered GridDisk DBFS_DG_CD_06_owtcel03 successfully altered GridDisk DBFS_DG_CD_07_owtcel03 successfully altered GridDisk DBFS_DG_CD_08_owtcel03 successfully altered GridDisk DBFS_DG_CD_09_owtcel03 successfully altered GridDisk DBFS_DG_CD_10_owtcel03 successfully altered GridDisk DBFS_DG_CD_11_owtcel03 successfully altered GridDisk RECO_OWT_CD_00_owtcel03 successfully altered GridDisk RECO_OWT_CD_01_owtcel03 successfully altered GridDisk RECO_OWT_CD_02_owtcel03 successfully altered GridDisk RECO_OWT_CD_03_owtcel03 successfully altered GridDisk RECO_OWT_CD_04_owtcel03 successfully altered GridDisk RECO_OWT_CD_05_owtcel03 successfully altered GridDisk RECO_OWT_CD_06_owtcel03 successfully altered GridDisk RECO_OWT_CD_07_owtcel03 successfully altered GridDisk RECO_OWT_CD_08_owtcel03 successfully altered GridDisk RECO_OWT_CD_09_owtcel03 successfully altered GridDisk RECO_OWT_CD_10_owtcel03 successfully altered GridDisk RECO_OWT_CD_11_owtcel03 successfully altered CellCLI> list griddisk attributes name, asmmodestatus ----wait become online DATA_OWT_CD_00_owtcel03 SYNCING DATA_OWT_CD_01_owtcel03 SYNCING DATA_OWT_CD_02_owtcel03 SYNCING DATA_OWT_CD_03_owtcel03 SYNCING DATA_OWT_CD_04_owtcel03 SYNCING DATA_OWT_CD_05_owtcel03 SYNCING DATA_OWT_CD_06_owtcel03 SYNCING DATA_OWT_CD_07_owtcel03 SYNCING DATA_OWT_CD_08_owtcel03 SYNCING DATA_OWT_CD_09_owtcel03 SYNCING DATA_OWT_CD_10_owtcel03 SYNCING DATA_OWT_CD_11_owtcel03 SYNCING DBFS_DG_CD_02_owtcel03 SYNCING DBFS_DG_CD_03_owtcel03 SYNCING DBFS_DG_CD_04_owtcel03 SYNCING DBFS_DG_CD_05_owtcel03 SYNCING DBFS_DG_CD_06_owtcel03 SYNCING DBFS_DG_CD_07_owtcel03 SYNCING DBFS_DG_CD_08_owtcel03 SYNCING DBFS_DG_CD_09_owtcel03 SYNCING DBFS_DG_CD_10_owtcel03 SYNCING DBFS_DG_CD_11_owtcel03 SYNCING RECO_OWT_CD_00_owtcel03 SYNCING RECO_OWT_CD_01_owtcel03 SYNCING RECO_OWT_CD_02_owtcel03 SYNCING RECO_OWT_CD_03_owtcel03 SYNCING RECO_OWT_CD_04_owtcel03 SYNCING RECO_OWT_CD_05_owtcel03 SYNCING RECO_OWT_CD_06_owtcel03 SYNCING RECO_OWT_CD_07_owtcel03 SYNCING RECO_OWT_CD_08_owtcel03 SYNCING RECO_OWT_CD_09_owtcel03 SYNCING RECO_OWT_CD_10_owtcel03 SYNCING RECO_OWT_CD_11_owtcel03 SYNCING</pre> CellCLI> create flashcache all Flash cache owtcel03_FLASHCACHE successfully created CellCLI> list cell detail name: owtcel03 bbuTempThreshold: 60 bbuChargeThreshold: 800 bmcType: IPMI cellVersion: OSS_11.2.3.2.1_LINUX.X64_130109 cpuCount: 24 diagHistoryDays: 7 fanCount: 12/12 fanStatus: normal flashCacheMode: writeback------------------Now mode become WRITEBACK id: 1110FMM1DG interconnectCount: 3 interconnect1: bondib0 iormBoost: 0.0 ipaddress1: 192.168.30.7/22 kernelVersion: 2.6.32-400.11.1.el5uek locatorLEDStatus: off makeModel: Oracle Corporation SUN FIRE X4270 M2 SERVER SAS metricHistoryDays: 7 notificationMethod: mail notificationPolicy: critical,warning,clear offloadEfficiency: 5,379.5 powerCount: 2/2 powerStatus: normal releaseVersion: 11.2.3.2.1 releaseTrackingBug: 14522699 smtpFrom: "Exadata OWT quarter" smtpFromAddr:*** smtpPort: 25 smtpPwd: ****** smtpServer:*** smtpToAddr: unixasr@** smtpUser: smtpUseSSL: FALSE snmpSubscriber: host=10.**,port=162,community=public,type=asr status: online temperatureReading: 20.0 temperatureStatus: normal upTime: 28 days, 13:52 cellsrvStatus: running msStatus: running rsStatus: running #### Do these steps for all exadata cells and then check the status: [root@owtcel01 ~]# dcli -l root -g cell_group "cellcli -e list cell detail" | grep "flashCacheMode" owtcel01: flashCacheMode: WriteBack owtcel02: flashCacheMode: WriteBack owtcel03: flashCacheMode: WriteBack owtcel04: flashCacheMode: WriteBack owtcel05: flashCacheMode: WriteBack owtcel06: flashCacheMode: WriteBack <pre><pre>
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