Re: [PATCH 5/9] mm/damon/{p,v}addr: skip folios already on the migration target node

[SJ Park <sj@kernel.org>]

On Mon,  2 Nov 2026 07:07:52 -0800 SJ Park <sj@kernel.org> wrote:

> From: Aveline Noir <jm5905938@gmail.com>
> 
> While measuring DAMOS migration overhead, I found that the target_nid
> path isolates folios already on the target node, then puts them back on
> the LRU without migrating them.
> 
> Skip them before isolation in vaddr and paddr, as the vaddr explicit
> destinations path already does.
> 
> In a synthetic same-node fvaddr test on a two-node x86-64 KVM guest (8
> interleaved runs per kernel), guest-kernel cycles fell by about 29% with
> 4 KiB regions and 90% with 16 MiB regions. Median kdamond CPU time fell
> by about 76% with 16 MiB regions, with no clear change with 4 KiB
> regions.
> 
> Cc: Bijan Tabatabai <bijan311@gmail.com>
> Signed-off-by: Aveline Noir <jm5905938@gmail.com>
> Signed-off-by: SJ Park <sj@kernel.org>

Somehow I dropped my R-b, sorry.  Andrew, could you please add below?

Reviewed-by: SJ Park <sj@kernel.org>


Thanks,
SJ

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