[Intel-wired-lan] [E1000-devel] i40e card Tx resets

[zhuyj <zyjzyj2000@gmail.com>]

On 03/15/2016 06:54 PM, Sowmini Varadhan wrote:
> On (03/15/16 16:55), zhuyj wrote:
>> Sorry. I explain this in details.
>> I have an similar problem. At first, I think it is related with tso.
>> Then I made tests with pktgen tools and found that this similar
>> problem still occurred whether
>> tso is enabled or not.
>>
>> So I suggest to make tests with pktgen tools to exclude tso.
>>
> I realize that TSO might not be the root cause (Tushar also
> pointed that out) but might just be triggering the issue...
>
> I dont think we need pktgen at this point- it's quite easy
> to reproduce this on commodity Haswell servers, and by installing
> the rds-stress from the rpm below:
>
> http://public-yum.oracle.com/repo/OracleLinux/OL6/ofed_UEK/x86_64//getPackageSource/rds-tools-2.0.7-1.12.el6.src.rpm
>
> To run it, set up 2 nodes  connected on i40e. I shall call them
> "client" and "server" though both will send traffic in the test
>
> Start the listener:
>   server# modprobe rds-tcp
>   server# rds-stress -r <server addr>
>
> Start the test:
>
>   client# modprobe rds-tcp
>   client# rds-stress -r <client addr> -s <server-addr> -q 256 -a 8192 -d16 -t16 -T30
>
> (all params are explained in the rds-stress man page)
>
> If you do this on ixgbe, you will see that the column for "tx+rx K/s"
> shows a steady throughput, whereas i40e numbers are bursty and low.
>
> Also, for i40e, you will see messages about TX hang on on the console.
>
> I think that, to find the root-cause, we need to see what is
> triggering the mdd error.
Hi,

Thanks for your reply.
Yesterday I made tests with rds-tools. It is very pity that I can not 
reproduce my problem with rds-tools.

But with pktgen tools, I can reproduce this problem easily. And I found 
that if I set the packet size to 17792 or less than this size,
this problem would not occur. But if I set the packet size > 17792, for 
example 17793, my problem would occur.

As such, maybe the packet size triggers my problem. I am not sure that 
the packet size will trigger your size.

Best Regards!
Zhu Yanjun
>
> Would be good if someone from Intel could provide some hints on
> how to do that (or try the above tests!)
>
> --Sowmini