Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751750AbaBHOaJ (ORCPT ); Sat, 8 Feb 2014 09:30:09 -0500 Received: from mail-pd0-f176.google.com ([209.85.192.176]:59378 "EHLO mail-pd0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751170AbaBHOaH (ORCPT ); Sat, 8 Feb 2014 09:30:07 -0500 Message-ID: <1391869805.10160.97.camel@edumazet-glaptop2.roam.corp.google.com> Subject: Re: 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] From: Eric Dumazet To: Thomas Glanzmann Cc: John Ogness , Eric Dumazet , "David S. Miller" , "Nicholas A. Bellinger" , target-devel , Linux Network Development , LKML Date: Sat, 08 Feb 2014 06:30:05 -0800 In-Reply-To: <20140208141905.GG20512@glanzmann.de> References: <1391727771.14985.41.camel@haakon3.risingtidesystems.com> <20140207051500.GB10916@glanzmann.de> <20140207075536.GB17815@glanzmann.de> <1391801597.1155.28.camel@haakon3.risingtidesystems.com> <20140207205142.GA8609@glanzmann.de> <20140208093808.GD16336@glanzmann.de> <1391865273.10160.76.camel@edumazet-glaptop2.roam.corp.google.com> <1391866389.10160.80.camel@edumazet-glaptop2.roam.corp.google.com> <1391867404.10160.88.camel@edumazet-glaptop2.roam.corp.google.com> <1391868816.10160.93.camel@edumazet-glaptop2.roam.corp.google.com> <20140208141905.GG20512@glanzmann.de> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2014-02-08 at 15:19 +0100, Thomas Glanzmann wrote: > Hello Eric, > I get the idea. However I'm a little bit confused, when I do a 'git grep > MSG_MORE' I don't see much references in the Linux kernel who use it at > all. So do you have an example for me where this flags needs to be > applied? Idea would be to set this flag when calling sendmsg() of the 48 bytes of the header, and not set it on the sendmsg() of the 512 bytes of the payload. iscsi_sw_tcp_xmit_segment() already adds MSG_MORE, but it would be nice to add a new _initial_ flags parameter to iscsi_sw_tcp_xmit_segment() -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/