Re: [PATCH v2] rdma: Modify rdma_conn_param.rnr_retry to 7

Philipp Reisner <[email protected]> Wed, 30 Jul 2025 16:23:35 +0200
Newsgroups dev.linux.lists.drbd-dev
Message-ID <CADGDV=Wd3p5VW9VyA_9nygWmFYYe4fgU0QF3t+Re8KJdZBLxKw@mail.gmail.com>
Thanks applied!

PS: I will continue to review your other patches in the next few days.

Best regards,
 Philipp

On Tue, Jul 8, 2025 at 9:53 AM zhengbing.huang <[email protected]>
wrote:

> During the sync process, we found that the
> IB_WC_RNR_RETRY_EXC_ERR error always occurred, and then
> the connection break. Then when the connection is restored,
> this error occurs again, enter a loop.
>
> When the IB_WC_RNR_RETRY_EXC_ERR error occurs,
> it indicates that there is no rx_desc at the receive side currently.
> Then we query that the current rnr_retry value is 0,
> meane there is no retry.
>
> So we modify rnr_retry to 7(max value), and the problem did not occur
> again.
>
> Signed-off-by: zhengbing.huang <[email protected]>
> ---
>  drbd/drbd_transport_rdma.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drbd/drbd_transport_rdma.c b/drbd/drbd_transport_rdma.c
> index 30edfaf96..14392a33b 100644
> --- a/drbd/drbd_transport_rdma.c
> +++ b/drbd/drbd_transport_rdma.c
> @@ -409,6 +409,7 @@ static struct rdma_conn_param dtr_conn_param = {
>         .responder_resources = 1,
>         .initiator_depth = 1,
>         .retry_count = 10,
> +       .rnr_retry_count  = 7,
>  };
>
>  static u32 dtr_cm_to_lkey(struct dtr_cm *cm)
> --
> 2.43.0
>
>