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			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			25 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| What:		/sys/kernel/mm/numa/
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| Date:		June 2021
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| Contact:	Linux memory management mailing list <linux-mm@kvack.org>
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| Description:	Interface for NUMA
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| 
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| What:		/sys/kernel/mm/numa/demotion_enabled
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| Date:		June 2021
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| Contact:	Linux memory management mailing list <linux-mm@kvack.org>
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| Description:	Enable/disable demoting pages during reclaim
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| 
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| 		Page migration during reclaim is intended for systems
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| 		with tiered memory configurations.  These systems have
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| 		multiple types of memory with varied performance
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| 		characteristics instead of plain NUMA systems where
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| 		the same kind of memory is found at varied distances.
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| 		Allowing page migration during reclaim enables these
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| 		systems to migrate pages from fast tiers to slow tiers
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| 		when the fast tier is under pressure.  This migration
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| 		is performed before swap.  It may move data to a NUMA
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| 		node that does not fall into the cpuset of the
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| 		allocating process which might be construed to violate
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| 		the guarantees of cpusets.  This should not be enabled
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| 		on systems which need strict cpuset location
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| 		guarantees.
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