On Thu, Sep 23, 2021 at 04:30:57PM +0200, Stefano Garzarella wrote:
> Commit d7ddd0a161 ("linux-aio: limit the batch size using
> `aio-max-batch` parameter") added a way to limit the batch size
> of Linux AIO backend for the entire AIO context.
> 
> The same AIO context can be shared by multiple devices, so
> latency-sensitive devices may want to limit the batch size even
> more to avoid increasing latency.
> 
> This series add the `aio-max-batch` option to the file backend,
> and use it in laio_co_submit() and laio_io_unplug() to limit the
> Linux AIO batch size more than the limit set by the AIO context.
> 
> Stefano Garzarella (3):
>   file-posix: add `aio-max-batch` option
>   linux-aio: add `dev_max_batch` parameter to laio_co_submit()
>   linux-aio: add `dev_max_batch` parameter to laio_io_unplug()
> 
>  qapi/block-core.json    |  5 +++++
>  include/block/raw-aio.h |  6 ++++--
>  block/file-posix.c      | 14 ++++++++++++--
>  block/linux-aio.c       | 38 +++++++++++++++++++++++++++-----------
>  4 files changed, 48 insertions(+), 15 deletions(-)

Sorry for the slow review. Comments posted!

Stefan