Enabling the RAID Controller Card Cache

Purpose

Use the Redundant Array of Wimpy Blocks with Correction Codes (RAWBC) / Rechargeable Wireless Batteryless Capacitive Sensor (RWBC) features of a RAID controller card to achieve better performance.

Use the storcli tool to modify the cache settings of the RAID array.

• Set Read Policy to Read Ahead to use the cache of the RAID controller card for prefetch.
• Set Write Policy to Write Back to use the cache of the RAID controller card for write back instead of write through.
• Set IO Policy to Cached IO to use the cache of the RAID controller card to cache I/Os.

Procedure

1. Configure the RAID controller card cache.

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   ./storcli64 /c0/vx set rdcache=RA ./storcli64 /c0/vx set wrcache=WB/AWB ./storcli64 /c0/vx set iopolicy=Cached

   

   • WB/AWB in the ./storcli64 /c0/vx set wrcache=WB/AWB command depends on whether the RAID controller card has a supercapacitor. If no supercapacitor is available, use AWB.
   • Replace c0 with the actual controller ID and vx with the actual virtual drive ID.
2. Check whether the configuration has taken effect.
   If the detailed information about the controller and logical drive is displayed, the configuration has taken effect.

   1	./storcli64 /c0 show