From mboxrd@z Thu Jan 1 00:00:00 1970 From: Karen Shaeffer Subject: Re: [RESEND] tuning linux for high network performance? Date: Thu, 24 Oct 2002 02:37:51 -0700 Sender: netdev-bounce@oss.sgi.com Message-ID: <20021024023751.A26024@synapse.neuralscape.com> References: <200210231218.18733.roy@karlsbakk.net> <20021023130101.GA646@outpost.ds9a.nl> <1035379308.5950.3.camel@rth.ninka.net> <200210231542.48673.roy@karlsbakk.net> <1035432669.9628.1.camel@rth.ninka.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@oss.sgi.com Return-path: To: "David S. Miller" Content-Disposition: inline In-Reply-To: <1035432669.9628.1.camel@rth.ninka.net>; from davem@rth.ninka.net on Wed, Oct 23, 2002 at 09:11:09PM -0700 Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org On Wed, Oct 23, 2002 at 09:11:09PM -0700, David S. Miller wrote: > On Wed, 2002-10-23 at 06:42, Roy Sigurd Karlsbakk wrote: > > As far as I've understood, sendfile() won't do much good with large files. Is > > this right? > > There is always a benefit to using sendfile(), when you use > sendfile() the cpu doesn't touch one byte of the data if > the network card support TX checksumming. The disk DMAs > to ram, then the net card DMAs from ram. Simple as that. Referring to: $ rpm -qf /usr/include/sys/sendfile.h glibc-devel-2.2.5-40 quoting "sendfile.h" #ifdef __USE_FILE_OFFSET64 # error " cannot be used with _FILE_OFFSET_BITS=64" #endif So, how does one use sendfile() for large files that are greater than 2 GBytes? Am I missing something? Thanks, Karen -- Karen Shaeffer Neuralscape; Santa Cruz, Ca. 95060 shaeffer@neuralscape.com http://www.neuralscape.com