Re: [PATCH 7/7] block/rbd: change request alignment to 1 byte

[Jason Dillaman]

On Sun, Dec 27, 2020 at 11:42 AM Peter Lieven <pl@kamp.de> wrote:
>
> since we implement byte interfaces and librbd supports aio on byte 
> granularity we can lift
> the 512 byte alignment.
>
> Signed-off-by: Peter Lieven <pl@kamp.de>
> ---
>  block/rbd.c | 2 --
>  1 file changed, 2 deletions(-)
>
> diff --git a/block/rbd.c b/block/rbd.c
> index 27b4404adf..8673e8f553 100644
> --- a/block/rbd.c
> +++ b/block/rbd.c
> @@ -223,8 +223,6 @@ done:
>  static void qemu_rbd_refresh_limits(BlockDriverState *bs, Error **errp)
>  {
>      BDRVRBDState *s = bs->opaque;
> -    /* XXX Does RBD support AIO on less than 512-byte alignment? */
> -    bs->bl.request_alignment = 512;

Just a suggestion, but perhaps improve discard alignment, max discard,
optimal alignment (if that's something QEMU handles internally) if not
overridden by the user.


>  #ifdef LIBRBD_SUPPORTS_WRITE_ZEROES
>      bs->bl.pwrite_zeroes_alignment = s->object_size;
>  #endif
> --
> 2.17.1
>
>


--
Jason