From: Neal Cardwell
Date: Tue, 24 Jul 2018 21:57:27 -0400
> On Tue, Jul 24, 2018 at 1:42 PM Lawrence Brakmo wrote:
>>
>> Note that without this fix the 99% latencies when doing 10KB RPCs
>> in a congested network using DCTCP are 40ms vs. 190us with the patch.
>> Also note that these 40ms high ta
On Tue, Jul 24, 2018 at 1:42 PM Lawrence Brakmo wrote:
>
> Note that without this fix the 99% latencies when doing 10KB RPCs
> in a congested network using DCTCP are 40ms vs. 190us with the patch.
> Also note that these 40ms high tail latencies started after commit
> 3759824da87b30ce7a35b4873b62b0
Note that without this fix the 99% latencies when doing 10KB RPCs in a
congested network using DCTCP are 40ms vs. 190us with the patch. Also note that
these 40ms high tail latencies started after commit
3759824da87b30ce7a35b4873b62b0ba38905ef5 in Jul 2015, which triggered the
bugs/features we a
On 07/24/2018 10:12 AM, Neal Cardwell wrote:
> On Tue, Jul 24, 2018 at 1:07 PM Yuchung Cheng wrote:
>>
>> On Mon, Jul 23, 2018 at 7:23 PM, Daniel Borkmann
>> wrote:
>>> Should this go to net tree instead where all the other fixes went?
>> I am neutral but this feels more like a feature improv
On Tue, Jul 24, 2018 at 1:07 PM Yuchung Cheng wrote:
>
> On Mon, Jul 23, 2018 at 7:23 PM, Daniel Borkmann wrote:
> > Should this go to net tree instead where all the other fixes went?
> I am neutral but this feels more like a feature improvement
I agree this feels like a feature improvement rath
On Mon, Jul 23, 2018 at 7:23 PM, Daniel Borkmann wrote:
>
> On 07/24/2018 04:15 AM, Neal Cardwell wrote:
> > On Mon, Jul 23, 2018 at 8:49 PM Lawrence Brakmo wrote:
> >>
> >> We observed high 99 and 99.9% latencies when doing RPCs with DCTCP. The
> >> problem is triggered when the last packet of a
On 07/24/2018 04:15 AM, Neal Cardwell wrote:
> On Mon, Jul 23, 2018 at 8:49 PM Lawrence Brakmo wrote:
>>
>> We observed high 99 and 99.9% latencies when doing RPCs with DCTCP. The
>> problem is triggered when the last packet of a request arrives CE
>> marked. The reply will carry the ECE mark caus
On Mon, Jul 23, 2018 at 8:49 PM Lawrence Brakmo wrote:
>
> We observed high 99 and 99.9% latencies when doing RPCs with DCTCP. The
> problem is triggered when the last packet of a request arrives CE
> marked. The reply will carry the ECE mark causing TCP to shrink its cwnd
> to 1 (because there ar
We observed high 99 and 99.9% latencies when doing RPCs with DCTCP. The
problem is triggered when the last packet of a request arrives CE
marked. The reply will carry the ECE mark causing TCP to shrink its cwnd
to 1 (because there are no packets in flight). When the 1st packet of
the next request a