Cache Settings - IBM BladeCenter S SAS RAID Controller Module Installation And User Manual

cache settings

Use this command to specify the cache settings.
Command arguments:
<CLI> cache -[get | set [-volumesetting -seqpostreadcmdsize [SIZE]
-seqreadaheadmargin [MARGIN] -writecachepolicy [off|on|default]
[-systemdefault] [-volumename [POOL:VOLUME]] | ctlrsetting
-writecachepolicy [on|off] ]
Where:
v [SIZE] - Indicates maximum sector count of single predictive read ahead.
v [MARGIN] - Defines number of sectors in read ahead buffer.
v [off|on|default] - Allows you to turn -writecachepolicy off or on or to use
v [POOL:VOLUME] - Indicates pool name and volume name. If pool name not
v [on|off] - Allows you to turn -writecachepolicy on or off when –ctlrsetting
The maximum sector count of a single predictive read ahead is
seqpostreadcmdsize. A value of 0 disables predictive read for this volume. A value
of 1-128 overrides the previous setting and represents a command transfer size that
is a multiple of 16Kb. A value of (0xFFFF) causes the default value to be used. The
number of sectors in the read ahead buffer is seqreadaheadmargin. This parameter
is ignored if the seqpostreadcmdsize is zero. The valid range is 1 to 0x7FFF. A
value of (0xFFFF) causes the default value to be used. The firmware sets the
writecachepolicy to specify the write cache policy. If none of the cache options are
provided, the current system default settings are used.
If you do not specify the -poolname, all volumes in the system will have their
settings modified. If you specify the -poolname but do not specify the -volumename,
the cache settings will be applied to all the volumes in the pool.
If you specify the –systemdefault option, the setting is used to change the system
default. System default is used to set the cache policy for a new volume that was
created with the cache policy set to default.
If you specify the –get option, the system default setting is displayed.
If you specify the –ctlrsetting option, the write cache settings for the controller
are set.
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IBM SAS RAID Controller Module: Installation and User's Guide IBM BladeCenter S SAS RAID Controller Module
with default settings.
specified, all system volume settings are modified; if pool name specified but
volume name is not specified, cache settings are applied to all volumes in pool.
option is specified.