mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 02:30:34 +02:00 
			
		
		
		
	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>
		
			
				
	
	
		
			22 lines
		
	
	
	
		
			786 B
		
	
	
	
		
			Text
		
	
	
	
	
	
			
		
		
	
	
			22 lines
		
	
	
	
		
			786 B
		
	
	
	
		
			Text
		
	
	
	
	
	
Linux SCSI Disk Driver (sd) Parameters
 | 
						|
======================================
 | 
						|
 | 
						|
cache_type (RW)
 | 
						|
---------------
 | 
						|
Enable/disable drive write & read cache.
 | 
						|
 | 
						|
 cache_type string          | WCE RCD | Write cache | Read cache
 | 
						|
----------------------------+---------+-------------+------------
 | 
						|
 write through              | 0   0   | off         | on
 | 
						|
 none                       | 0   1   | off         | off
 | 
						|
 write back                 | 1   0   | on          | on
 | 
						|
 write back, no read (daft) | 1   1   | on          | off
 | 
						|
 | 
						|
To set cache type to "write back" and save this setting to the drive:
 | 
						|
 | 
						|
  # echo "write back" > cache_type
 | 
						|
 | 
						|
To modify the caching mode without making the change persistent, prepend
 | 
						|
"temporary " to the cache type string. E.g.:
 | 
						|
 | 
						|
  # echo "temporary write back" > cache_type
 |