mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
To: Aaron Lu <aaron.lu@intel.com>
Cc: Xin Long <lucien.xin@gmail.com>,
	kernel test robot <xiaolong.ye@intel.com>,
	Stephen Rothwell <sfr@canb.auug.org.au>,
	lkp@01.org, "David S. Miller" <davem@davemloft.net>,
	LKML <linux-kernel@vger.kernel.org>,
	"Chen, Tim C" <tim.c.chen@intel.com>,
	Huang Ying <ying.huang@intel.com>
Subject: Re: [LKP] [lkp] [sctp] a6c2f79287: netperf.Throughput_Mbps -37.2% regression
Date: Mon, 22 Aug 2016 18:44:06 -0300	[thread overview]
Message-ID: <9ddf610d-c819-14ec-42b0-0ee61c0de173@gmail.com> (raw)
In-Reply-To: <20160819072420.GA1167@aaronlu.sh.intel.com>

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.

Regards,
Marcelo

  reply	other threads:[~2016-08-22 21:44 UTC|newest]

Thread overview: 36+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-07-27  1:54 kernel test robot
2016-07-28  7:01 ` Xin Long
2016-08-05  3:31   ` [LKP] " Aaron Lu
2016-08-05 11:53     ` Xin Long
2016-08-08  2:10       ` Aaron Lu
2016-08-16  2:38         ` Aaron Lu
2016-08-16  8:02         ` Xin Long
2016-08-16  8:30           ` Aaron Lu
2016-08-16  8:51           ` Aaron Lu
2016-08-16  9:56             ` Xin Long
2016-08-17  5:04               ` Aaron Lu
2016-08-17  5:34                 ` Xin Long
2016-08-17  5:34                 ` Aaron Lu
2016-08-17  5:41                   ` Xin Long
2016-08-17  6:14                     ` Aaron Lu
2016-08-17  6:37                       ` Aaron Lu
2016-08-17  6:42                         ` Aaron Lu
2016-08-17  7:35                         ` Xin Long
2016-08-17  7:42                           ` Aaron Lu
2016-08-17  7:53                             ` Aaron Lu
2016-08-17  8:02                             ` Xin Long
2016-08-17  8:48                               ` Aaron Lu
2016-08-17  8:58                                 ` Xin Long
2016-08-17  9:20                                   ` Aaron Lu
2016-08-17 18:06                                     ` Xin Long
2016-08-18  3:21                                       ` Aaron Lu
2016-08-18 12:45                                         ` Xin Long
2016-08-19  5:29                                           ` Aaron Lu
2016-08-19  7:19                                             ` Marcelo Ricardo Leitner
2016-08-19  7:24                                               ` Aaron Lu
2016-08-22 21:44                                                 ` Marcelo Ricardo Leitner [this message]
2016-08-23  9:19                                                   ` Aaron Lu
2016-09-30  7:05                                                   ` Aaron Lu
2016-10-03  2:32                                                     ` Xin Long
2016-10-09  7:41                                                       ` Aaron Lu
2016-08-16 18:34             ` Xin Long

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=9ddf610d-c819-14ec-42b0-0ee61c0de173@gmail.com \
    --to=marcelo.leitner@gmail.com \
    --cc=aaron.lu@intel.com \
    --cc=davem@davemloft.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lkp@01.org \
    --cc=lucien.xin@gmail.com \
    --cc=sfr@canb.auug.org.au \
    --cc=tim.c.chen@intel.com \
    --cc=xiaolong.ye@intel.com \
    --cc=ying.huang@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®