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NOTE: In Cluster mode, PERC 3/DC allows write- through cache policy only.

Stripe Size specifies the size of the segments written to each disk in a RAID 1 or 5 logical drive. You can set the stripe size to 2 KB, 4 KB,

8 KB, 16 KB, 32 KB, 64 KB, or 128 KB. A larger stripe size produces better read performance, especially if your computer does mostly sequential reads. If you are sure that your computer does random read requests more often, choose a small stripe size. The default is 64 KB.

12Set the Write Policy from the Advanced Menu.

Write Policy sets the caching method to write-back or write-through.

In Write-backcaching, the controller sends a data transfer completion signal to the host when the controller cache has received all the data in a transaction. This setting is recommended in standard mode.

In Write-throughcaching, the controller sends a data transfer completion signal to the host when the disk subsystem has received all the data in a transaction. This is the default setting if cluster mode is enabled.

Write-throughcaching has a data security advantage over write-backcaching. Write-backcaching has a performance advantage over write- through caching.

13Set the Read Policy from the Advanced Menu.

The Read-aheadoption enables the SCSI read-ahead feature for the logical drive. You can set this parameter to No-Read-Ahead, Read- ahead, or Adaptive. Adaptive is the default setting.

No-Read-Aheadspecifies that the controller does not use read- ahead for the current logical drive.

Read-aheadspecifies that the controller uses read-ahead for the current logical drive.

Adaptive specifies that the controller begins using read-ahead if the two most recent disk accesses occurred in sequential sectors. If all read requests are random, the algorithm reverts to No-Read- Ahead, however, all requests are still evaluated for possible sequential operation.

14Set the Read Policy from the Advanced Menu.

Cache Policy applies to reads on a specific logical drive. It does not affect the Read-aheadcache.

Cached I/O specifies that all reads are buffered in cache memory.

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