Return-Path: Received: from fieldses.org ([173.255.197.46]:44214 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756027AbbJHNAJ (ORCPT ); Thu, 8 Oct 2015 09:00:09 -0400 Date: Thu, 8 Oct 2015 09:00:08 -0400 From: Bruce Fields To: Trond Myklebust Cc: Linux NFS Mailing List Subject: Re: [PATCH] SUNRPC: Use MSG_SENDPAGE_NOTLAST when calling sendpage() Message-ID: <20151008130008.GB32078@fieldses.org> References: <1444240482-11287-1-git-send-email-trond.myklebust@primarydata.com> <20151007200831.GB27924@fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, Oct 08, 2015 at 08:35:02AM -0400, Trond Myklebust wrote: > On Wed, Oct 7, 2015 at 7:17 PM, Trond Myklebust > wrote: > > On Wed, Oct 7, 2015 at 4:08 PM, Bruce Fields wrote: > >> On Wed, Oct 07, 2015 at 01:54:42PM -0400, Trond Myklebust wrote: > >>> If we're sending more pages via kernel_sendpage(), then set > >>> MSG_SENDPAGE_NOTLAST. > >> > >> Given that we've survived without this a while, I assume this is a hint > >> that may provide better performance in some cases (have you seen that?) > >> and that it doesn't have to be 100% correct? > > > > See the original motivation in: > > > > commit 2f5338442425 ("tcp: allow splice() to build full TSO packets") > > > > and the later bugfix (which actually introduces MSG_SENDPAGE_NOTLAST): > > > > commit 35f9c09fe9c7 ("tcp: tcp_sendpages() should call tcp_push() once") > > > >> In which case, looks fine, will queue up for 4.4.... > > > > Sure. It's a minor performance enhancement, so there is no immediate rush. > > Actually, please let me split this into 2 subpatches; one for the > sunrpc server code and one for the client. It would make it easier for > me if I could keep the client performance stuff in one branch. Sure, makes sense.--b.