A problem on TCP in High RTT Environment.

[Michael Tuexen]

On 11 Aug 2014, at 09:08, Eggert, Lars <lars at netapp.com> wrote:

> Hi,
> 
> On 2014-8-10, at 5:48, Niu Zhixiong <kaiaixi at gmail.com> wrote:
>> I am using Intel I350-T4 NIC.
> 
> igb driver?
> 
> I've been having weird issues with this driver under 10-RELEASE, too. On one machine, I had to limit hw.igb.num_queues=2 in order to get any sort of useful connectivity. On another machine, I had to severely bump kern.ipc.nmbclusters & friends. I'm not sure this is the issue here, since SCTP seems to be working OK, but I'm not trusting igb NICs at the moment.
Was there any suspicious output provided by netstat -m when the problems occur?

Best regards
Michael
> 
> Lars