Re: [PATCH v3 09/15] system/ram-discard-manager: implement replay via is_populated iteration

[David Hildenbrand <david@kernel.org>]

On 2/26/26 14:59, marcandre.lureau@redhat.com wrote:
> From: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> Replace the source-level replay wrappers with a new
> replay_by_populated_state() helper that iterates the section at
> min-granularity, calls is_populated() for each chunk, and aggregates
> consecutive chunks of the same state before invoking the callback.
> 
> This moves the iteration logic from individual sources into the manager,
> preparing for multi-source aggregation where the manager must combine
> state from multiple sources anyway.
> 
> The replay_populated/replay_discarded vtable entries in
> RamDiscardSourceClass are no longer called but remain in the interface
> for now; they will be removed in follow-up commits along with the
> now-dead source implementations.
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---

Isn't it significantly more expensive for large guests to possibly
iterate in 4k granularity?

The nice thing about the old implementation was that we could just scan
a bitmap, that is ideally in 2M granularity.

-- 
Cheers,

David