From: Jon Maloy <jon.ma...@ericsson.com> Date: Thu, 30 Nov 2017 16:47:25 +0100
> When sending node local messages the code is using an 'mtu' of 66060 > bytes to avoid unnecessary fragmentation. During situations of low > memory tipc_msg_build() may sometimes fail to allocate such large > buffers, resulting in unnecessary send failures. This can easily be > remedied by falling back to a smaller MTU, and then reassemble the > buffer chain as if the message were arriving from a remote node. > > At the same time, we change the initial MTU setting of the broadcast > link to a lower value, so that large messages always are fragmented > into smaller buffers even when we run in single node mode. Apart from > obtaining the same advantage as for the 'fallback' solution above, this > turns out to give a significant performance improvement. This can > probably be explained with the __pskb_copy() operation performed on the > buffer for each recipient during reception. We found the optimal value > for this, considering the most relevant skb pool, to be 3744 bytes. > > Acked-by: Ying Xue <ying....@ericsson.com> > Signed-off-by: Jon Maloy <jon.ma...@ericsson.com> Applied, thanks Jon.
