18d595bf9d
Add a file for documenting SCSI sd module parameters and describe the cache_type setting. [mkp: tweaked text a bit] Signed-off-by: Weiping Zhang <zhangweiping@didichuxing.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
23 lines
786 B
Plaintext
23 lines
786 B
Plaintext
Linux SCSI Disk Driver (sd) Parameters
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======================================
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cache_type (RW)
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---------------
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Enable/disable drive write & read cache.
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cache_type string | WCE RCD | Write cache | Read cache
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----------------------------+---------+-------------+------------
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write through | 0 0 | off | on
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none | 0 1 | off | off
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write back | 1 0 | on | on
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write back, no read (daft) | 1 1 | on | off
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To set cache type to "write back" and save this setting to the drive:
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# echo "write back" > cache_type
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To modify the caching mode without making the change persistent, prepend
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"temporary " to the cache type string. E.g.:
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# echo "temporary write back" > cache_type
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