IBM BladeCenter S SAS RAID Controller Module, Инструкция по установке и эксплуатации

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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
with default settings.
v [POOL:VOLUME]
- Indicates pool name and volume name. If pool name not
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.
v [on|off]
- Allows you to turn
-writecachepolicy
on or off when
–ctlrsetting
option is specified.
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