Avago Technologies 3ware SAS 9750-4i - Manual (Page 100)

Chapter 2. CLI Syntax Reference
92 3ware SATA+SAS RAID Controller Card CLI Guide, Version 10.0
/c x /u x set cache=on|off [quiet]
This command is the same as “/cx/ux set wrcache=on|off [quiet]”. Please see
below for details.
/c x /u x set wrcache=on|off [quiet]
This command allows you to turn on or off the write cache for a specified unit
/cx/ux. This feature is supported on all controllers.
By default, write cache is on.
Write cache includes the disk drive cache and controller cache.
When write cache is on, data will be stored in 3ware controller cache and
drive cache before the data is committed to disk. This allows the system to
process multiple write commands at the same time, thus improving
performance. However when data is stored in cache, it could be lost if a power
failure occurs. With a Battery Backup Unit (BBU) installed, the data stored on
the 3ware controller can be restored.
The following table shows the supported RAID types for write caching as a
function of controller model and logical unit type. N/A (Not Applicable)
refers to cases where the given logical unit type is not supported on a
particular controller model.
The quiet attribute turns off interactive mode, where no confirmation is
requested to proceed.
/c x /u x set rdcache=basic|intelligent|off
This command allows you to set the read cache to either Basic, Intelligent, or
Off on a specified unit. Setting this to Intelligent enables both Intelligent
Mode features and Basic Mode features. Setting it to Off disables both.
This command is supported on the 9750, 9690SA, and 9650SE controllers.
This feature is supported in all types of RAID units.
Table 12: Supported RAID Types for Write Caching
Model R0 R1 R5 R6 R10 R50 Single Spare
7K/8K Yes Yes Yes N/A Yes N/A N/A No
9000 a
a. Models 9500S, 9550SX, and 9590SE
Yes Yes Yes N/A Yes Yes Yes No
9750,
9690SA,
and
9650SE Yes Yes Yes Yes Yes Yes Yes No