Re: [PATCH 0/7] Accelerate page migration with batch copying and hardware offload

[Huang, Ying]

"David Hildenbrand (Arm)" <david@xxxxxxxxxx> writes:

> On 4/28/26 17:50, Shivank Garg wrote:
>> This is the fifth RFC of the patchset to enhance page migration by

[snip]
>
>> 
>> 3. Per-caller offload selection: Today eligibility is by migrate_reason
>>    only. Some are latency-tolerant, others may be not. Is reason the
>>    right granularity, or do we want a per-caller hint?
>
> Isn't it sufficient to just do it based on the #folios or sth like that?
>
> If someone migrates a handful of folios, latency is likely more important (and
> batching less beneficial).
>
> I'd assume when migrating many folios, batching could just always be done. Or
> what's the concern?

IIUC, for callers like migrate_pages syscall, it's possible that almost all
folios of a process are passed to migrate_pages().  However, I think that
we still need to keep the folio inaccessible time reasonable.

[snip]

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Best Regards,
Huang, Ying