Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1493918 > unrolled thread

Re: [LKP] [lkp] [sctp] a6c2f79287: netperf.Throughput_Mbps -37.2% regression

Started byAaron Lu <aaron.lu@intel.com>
First post2016-09-30 09:10 +0200
Last post2016-10-09 09:50 +0200
Articles 3 — 2 participants

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.


Contents

  Re: [LKP] [lkp] [sctp] a6c2f79287: netperf.Throughput_Mbps -37.2%  regression Aaron Lu <aaron.lu@intel.com> - 2016-09-30 09:10 +0200
    Re: [LKP] [lkp] [sctp] a6c2f79287: netperf.Throughput_Mbps -37.2% regression Xin Long <lucien.xin@gmail.com> - 2016-10-03 04:40 +0200
      Re: [LKP] [lkp] [sctp] a6c2f79287: netperf.Throughput_Mbps -37.2%  regression Aaron Lu <aaron.lu@intel.com> - 2016-10-09 09:50 +0200

#1493918 — Re: [LKP] [lkp] [sctp] a6c2f79287: netperf.Throughput_Mbps -37.2% regression

FromAaron Lu <aaron.lu@intel.com>
Date2016-09-30 09:10 +0200
SubjectRe: [LKP] [lkp] [sctp] a6c2f79287: netperf.Throughput_Mbps -37.2% regression
Message-ID<sn07f-73F-15@gated-at.bofh.it>
On 08/23/2016 05:44 AM, Marcelo Ricardo Leitner wrote:
> Em 19-08-2016 04:24, Aaron Lu escreveu:
>> On Fri, Aug 19, 2016 at 04:19:39AM -0300, Marcelo Ricardo Leitner wrote:
>>> Hi,
>>>
>>> Em 19-08-2016 02:29, Aaron Lu escreveu:
>>> ...
>>>> It doesn't look insane and sctp_wait_for_sndbuf may actually have
>>>> something to do with a larger sctp_chunk I suppose?
>>>>
>>>> The same perf record doesn't capture any sample for the good commit,
>>>> which suggests the nerperf process doesn't sleep in sctp_wait_for_sndbuf.
>>>
>>> Ahhh yes! It does, and then it would mean your txbuf is too small for the
>>> chunk sizes you're using (sctp tests option -m).
>>>
>>> What's your netperf cmdline again please?
>>
>> netperf -4 -t SCTP_STREAM_MANY -c -C -l 300 -- -m 10K -H 127.0.0.1
>>
>> Is the 10K used here a problem? If so, can you suggest a proper value
>> for our netperf performance test? Thanks.
> 
> We're still working on this. Xin could reproduce it on an i3 too, but 
> I'm afraid this commit just unmasked an issue in there. You're 
> overloading the CPU by too much when spawning 8 parallel netperf's on a 
> 4-core system, seems that commit a6c2f79287 was that last rock that made 
> it slip into a precipice. sctp's cwnd and rwnd management are not as 
> good as tcp's and now it seems you're triggering a corner case.
> 
> I hope to have more soon.

I wonder if there is any update on this issue?

Thanks,
Aaron

[toc] | [next] | [standalone]


#1494678 — Re: [LKP] [lkp] [sctp] a6c2f79287: netperf.Throughput_Mbps -37.2% regression

FromXin Long <lucien.xin@gmail.com>
Date2016-10-03 04:40 +0200
SubjectRe: [LKP] [lkp] [sctp] a6c2f79287: netperf.Throughput_Mbps -37.2% regression
Message-ID<so1kD-6Cz-69@gated-at.bofh.it>
In reply to#1493918
On Fri, Sep 30, 2016 at 3:05 PM, Aaron Lu <aaron.lu@intel.com> wrote:
> On 08/23/2016 05:44 AM, Marcelo Ricardo Leitner wrote:
>> Em 19-08-2016 04:24, Aaron Lu escreveu:
>>> On Fri, Aug 19, 2016 at 04:19:39AM -0300, Marcelo Ricardo Leitner wrote:
>>>> Hi,
>>>>
>>>> Em 19-08-2016 02:29, Aaron Lu escreveu:
>>>> ...
>>>>> It doesn't look insane and sctp_wait_for_sndbuf may actually have
>>>>> something to do with a larger sctp_chunk I suppose?
>>>>>
>>>>> The same perf record doesn't capture any sample for the good commit,
>>>>> which suggests the nerperf process doesn't sleep in sctp_wait_for_sndbuf.
>>>>
>>>> Ahhh yes! It does, and then it would mean your txbuf is too small for the
>>>> chunk sizes you're using (sctp tests option -m).
>>>>
>>>> What's your netperf cmdline again please?
>>>
>>> netperf -4 -t SCTP_STREAM_MANY -c -C -l 300 -- -m 10K -H 127.0.0.1
>>>
>>> Is the 10K used here a problem? If so, can you suggest a proper value
>>> for our netperf performance test? Thanks.
>>
>> We're still working on this. Xin could reproduce it on an i3 too, but
>> I'm afraid this commit just unmasked an issue in there. You're
>> overloading the CPU by too much when spawning 8 parallel netperf's on a
>> 4-core system, seems that commit a6c2f79287 was that last rock that made
>> it slip into a precipice. sctp's cwnd and rwnd management are not as
>> good as tcp's and now it seems you're triggering a corner case.
>>
>> I hope to have more soon.
>
> I wonder if there is any update on this issue?
>
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

be4947b sctp: change to check peer prsctp_capable when using prsctp polices
0605483 sctp: remove prsctp_param from sctp_chunk
73dca12 sctp: move sent_count to the memory hole in sctp_chunk

These three commit can avoid this issue by recovering sctp_chunk size.

[toc] | [prev] | [next] | [standalone]


#1497880

FromAaron Lu <aaron.lu@intel.com>
Date2016-10-09 09:50 +0200
Message-ID<sqh1T-1k6-1@gated-at.bofh.it>
In reply to#1494678
On Mon, Oct 03, 2016 at 10:32:04AM +0800, Xin Long wrote:
> On Fri, Sep 30, 2016 at 3:05 PM, Aaron Lu <aaron.lu@intel.com> wrote:
> > On 08/23/2016 05:44 AM, Marcelo Ricardo Leitner wrote:
> >> Em 19-08-2016 04:24, Aaron Lu escreveu:
> >>> On Fri, Aug 19, 2016 at 04:19:39AM -0300, Marcelo Ricardo Leitner wrote:
> >>>> Hi,
> >>>>
> >>>> Em 19-08-2016 02:29, Aaron Lu escreveu:
> >>>> ...
> >>>>> It doesn't look insane and sctp_wait_for_sndbuf may actually have
> >>>>> something to do with a larger sctp_chunk I suppose?
> >>>>>
> >>>>> The same perf record doesn't capture any sample for the good commit,
> >>>>> which suggests the nerperf process doesn't sleep in sctp_wait_for_sndbuf.
> >>>>
> >>>> Ahhh yes! It does, and then it would mean your txbuf is too small for the
> >>>> chunk sizes you're using (sctp tests option -m).
> >>>>
> >>>> What's your netperf cmdline again please?
> >>>
> >>> netperf -4 -t SCTP_STREAM_MANY -c -C -l 300 -- -m 10K -H 127.0.0.1
> >>>
> >>> Is the 10K used here a problem? If so, can you suggest a proper value
> >>> for our netperf performance test? Thanks.
> >>
> >> We're still working on this. Xin could reproduce it on an i3 too, but
> >> I'm afraid this commit just unmasked an issue in there. You're
> >> overloading the CPU by too much when spawning 8 parallel netperf's on a
> >> 4-core system, seems that commit a6c2f79287 was that last rock that made
> >> it slip into a precipice. sctp's cwnd and rwnd management are not as
> >> good as tcp's and now it seems you're triggering a corner case.
> >>
> >> I hope to have more soon.
> >
> > I wonder if there is any update on this issue?
> >
> git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> 
> be4947b sctp: change to check peer prsctp_capable when using prsctp polices
> 0605483 sctp: remove prsctp_param from sctp_chunk
> 73dca12 sctp: move sent_count to the memory hole in sctp_chunk
> 
> These three commit can avoid this issue by recovering sctp_chunk size.

Thanks for the update, I just confirmed the throughput is back on my
desktop.

[toc] | [prev] | [standalone]


Back to top | Article view | linux.kernel


csiph-web