netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Thomas Glanzmann <thomas@glanzmann.de>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>,
	John Ogness <john.ogness@linutronix.de>,
	Eric Dumazet <edumazet@google.com>,
	"David S. Miller" <davem@davemloft.net>,
	target-devel <target-devel@vger.kernel.org>,
	Linux Network Development <netdev@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] This extends tx_data and and iscsit_do_tx_data with the additional parameter flags and avoids sending multiple TCP packets in iscsit_fe_sendpage_sg
Date: Mon, 10 Feb 2014 22:14:45 +0100	[thread overview]
Message-ID: <20140210211445.GE19621@glanzmann.de> (raw)
In-Reply-To: <1392066100.6615.55.camel@edumazet-glaptop2.roam.corp.google.com>

Hello Eric,

> Hmm.. I was not aware of high RTT for some packets.
> Can you spot this on the pcap you provided ?

with the latest patch as in:

(node-62) [~/work/linux-2.6] git diff | pbot
http://pbot.rmdir.de/CQwqI6b7wJProw_xaukmEg

with net.ipv4.tcp_min_tso_segs=2 we had this pcap:
https://thomas.glanzmann.de/tmp/tcp_auto_corking_on_patched_tcp_more_notlast.pcap.bz2
And here is the RTT TCP graph:
Wireshark > Statistics > TCP Stream Graph > Round Trip Time Graph
https://thomas.glanzmann.de/tmp/screenshot-mini-2014-02-10-22_04_30.png

with net.ipv4.tcp_min_tso_segs=8 we have this pcap:
https://thomas.glanzmann.de/tmp/tcp_auto_corking_on_patched_tcp_more_notlast_min_tso_segs_8.pcap.bz2
And here is the RTT TCP graph:
Wireshark > Statistics > TCP Stream Graph > Round Trip Time Graph

This gives us 0.0015 seconds RTT (1.5 ms)

Without TCP autocorking we had 0.0005 (0.5 ms).

https://thomas.glanzmann.de/tmp/screenshot-mini-2014-02-08-09:53:17.png

Cheers,
        Thomas

  reply	other threads:[~2014-02-10 21:14 UTC|newest]

Thread overview: 42+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20140206153640.GB4103@glanzmann.de>
     [not found] ` <1391727771.14985.41.camel@haakon3.risingtidesystems.com>
     [not found]   ` <20140207051500.GB10916@glanzmann.de>
     [not found]     ` <20140207075536.GB17815@glanzmann.de>
     [not found]       ` <1391801597.1155.28.camel@haakon3.risingtidesystems.com>
     [not found]         ` <20140207205142.GA8609@glanzmann.de>
2014-02-08  9:18           ` REGRESSION f54b311142a92ea2e42598e347b84e1655caf8e3 tcp auto corking slows down iSCSI file system creation by factor of 70 [WAS: 4 TB VMFS creation takes 15 minutes vs 26 seconds] Thomas Glanzmann
2014-02-08  9:19             ` [PATCH] tcp: disable auto corking by default Thomas Glanzmann
2014-02-08 15:04               ` Eric Dumazet
2014-02-08 16:55                 ` Thomas Glanzmann
2014-02-08 17:12                   ` Eric Dumazet
2014-02-08 17:20                     ` Thomas Glanzmann
2014-02-08  9:23           ` REGRESSION f54b311142a92ea2e42598e347b84e1655caf8e3 tcp auto corking slows down iSCSI file system creation by factor of 70 [WAS: 4 TB VMFS creation takes 15 minutes vs 26 seconds] Thomas Glanzmann
2014-02-08  9:38           ` Thomas Glanzmann
2014-02-08 13:14             ` Eric Dumazet
2014-02-08 13:33               ` Eric Dumazet
2014-02-08 13:38                 ` Thomas Glanzmann
2014-02-08 13:50                 ` Eric Dumazet
2014-02-08 14:13                   ` Eric Dumazet
2014-02-08 14:19                     ` Thomas Glanzmann
2014-02-08 14:30                       ` Eric Dumazet
2014-02-08 15:00                         ` Thomas Glanzmann
2014-02-08 15:06                           ` Eric Dumazet
2014-02-08 16:57                             ` Thomas Glanzmann
2014-02-08 17:08                               ` Eric Dumazet
2014-02-08 17:15                                 ` Thomas Glanzmann
2014-02-08 19:12                                   ` Eric Dumazet
2014-02-08 21:36                                     ` Thomas Glanzmann
2014-02-09  0:15                                       ` Eric Dumazet
2014-02-09  7:45                                         ` Thomas Glanzmann
2014-02-09  7:40                                     ` RFC: Set MSG_MORE in iscsit_fe_sendpage_sg to avoid sending multiple TCP packets instead of one Thomas Glanzmann
2014-02-09  7:42                                       ` [PATCH] This extends tx_data and and iscsit_do_tx_data with the additional parameter flags and avoids sending multiple TCP packets in iscsit_fe_sendpage_sg Eric Dumazet
2014-02-09 12:30                                         ` Eric Dumazet
2014-02-09 15:07                                           ` Thomas Glanzmann
2014-02-10 18:58                                           ` Nicholas A. Bellinger
2014-02-10 20:56                                             ` Thomas Glanzmann
2014-02-10 21:01                                               ` Eric Dumazet
2014-02-10 21:14                                                 ` Thomas Glanzmann [this message]
2014-02-08 13:37               ` REGRESSION f54b311142a92ea2e42598e347b84e1655caf8e3 tcp auto corking slows down iSCSI file system creation by factor of 70 [WAS: 4 TB VMFS creation takes 15 minutes vs 26 seconds] Thomas Glanzmann
2014-02-08 13:53                 ` Eric Dumazet
2014-02-08 13:58                   ` Thomas Glanzmann
2014-02-08 14:09                 ` Eric Dumazet
2014-02-08 14:12                   ` Thomas Glanzmann
2014-02-17 14:08                   ` Thomas Glanzmann
2014-02-17 15:26                     ` Eric Dumazet
2014-02-17 15:32                       ` Thomas Glanzmann
2014-02-17 15:46                         ` Eric Dumazet
2014-02-17 15:46                           ` Thomas Glanzmann

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=20140210211445.GE19621@glanzmann.de \
    --to=thomas@glanzmann.de \
    --cc=davem@davemloft.net \
    --cc=edumazet@google.com \
    --cc=eric.dumazet@gmail.com \
    --cc=john.ogness@linutronix.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=nab@linux-iscsi.org \
    --cc=netdev@vger.kernel.org \
    --cc=target-devel@vger.kernel.org \
    /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;
as well as URLs for NNTP newsgroup(s).