From: Adam Urban <adam.urban@appleguru.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com>,
Network Development <netdev@vger.kernel.org>
Subject: Re: Kernel UDP behavior with missing destinations
Date: Thu, 16 May 2019 12:32:35 -0400 [thread overview]
Message-ID: <CABUuw67crf5yb0G_KRR94WLBP8YYLgABBgv1SFW0SvKB_ntK4w@mail.gmail.com> (raw)
In-Reply-To: <18aefee7-4c47-d330-c6c1-7d1442551fa6@gmail.com>
Eric, thanks. Increasing wmem_default from 229376 to 2293760 indeed
makes the issue go away on my test bench. What's a good way to
determine the optimal value here? I assume this is in bytes and needs
to be large enough so that the SO_SNDBUF doesn't fill up before the
kernel drops the packets. How often does that happen?
On Thu, May 16, 2019 at 12:14 PM Eric Dumazet <eric.dumazet@gmail.com> wrote:
>
>
>
> On 5/16/19 9:05 AM, Eric Dumazet wrote:
>
> > We probably should add a ttl on arp queues.
> >
> > neigh_probe() could do that quite easily.
> >
>
> Adam, all you need to do is to increase UDP socket sndbuf.
>
> Either by increasing /proc/sys/net/core/wmem_default
>
> or using setsockopt( ... SO_SNDBUF ... )
>
next prev parent reply other threads:[~2019-05-16 16:32 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-15 19:56 Kernel UDP behavior with missing destinations Adam Urban
2019-05-16 14:47 ` Willem de Bruijn
2019-05-16 15:43 ` Adam Urban
2019-05-16 16:05 ` Eric Dumazet
2019-05-16 16:14 ` Eric Dumazet
2019-05-16 16:32 ` Adam Urban [this message]
2019-05-16 17:03 ` Eric Dumazet
2019-05-16 21:42 ` Adam Urban
2019-05-17 0:27 ` Adam Urban
2019-05-17 3:22 ` Willem de Bruijn
2019-05-17 12:57 ` David Laight
2019-05-17 13:20 ` Willem de Bruijn
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