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Re: [PATCH v6 03/16] libs/guest: Reduce number of I/O vectors in write_batch
- To: Frediano Ziglio <freddy77@xxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxxx
- From: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
- Date: Tue, 30 Jun 2026 17:46:55 +0100
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- Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>, Frediano Ziglio <frediano.ziglio@xxxxxxxxxx>, Jan Beulich <jbeulich@xxxxxxxx>, Roger Pau Monné <roger.pau@xxxxxxxxxx>, Teddy Astie <teddy.astie@xxxxxxxxxx>, Anthony PERARD <anthony.perard@xxxxxxxxxx>, Juergen Gross <jgross@xxxxxxxx>
- Delivery-date: Tue, 30 Jun 2026 16:47:11 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
This has the same exact subject as the prior patch.
Either it wants merging, as they're both in the same function, or the
subject wants to be different. Even a "Further ..." prefix would help.
On 19/06/2026 2:04 pm, Frediano Ziglio wrote:
> Each page was sent using a different iovec item. This potentially exceed
> Linux maximum (1024).
Linux cannot have a maximum of 1024 because this has been working fine
for a decade using 1028 in the common case.
> Coalesce adjacent IO vector elements to attempt to reduce the number of
> overall IO vectors for each operation.
> Also some implementation (MiniOS) emulate writev with multiple write calls.
>
> Signed-off-by: Frediano Ziglio <frediano.ziglio@xxxxxxxxxx>
> Reviewed-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
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