From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarek Poplawski Subject: Re: Splice status Date: Mon, 26 Jul 2010 22:37:52 +0200 Message-ID: <4C4DF220.1050307@gmail.com> References: <1278334254.2877.158.camel@edumazet-laptop> <1278388580.2466.305.camel@edumazet-laptop> <1279030308.2634.349.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Eric Dumazet , Changli Gao , Jens Axboe , "netdev@vger.kernel.org" To: Ofer Heifetz Return-path: Received: from mail-bw0-f46.google.com ([209.85.214.46]:61350 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755326Ab0GZUiF (ORCPT ); Mon, 26 Jul 2010 16:38:05 -0400 Received: by bwz1 with SMTP id 1so2992240bwz.19 for ; Mon, 26 Jul 2010 13:38:03 -0700 (PDT) In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: Ofer Heifetz wrote, On 25.07.2010 16:47: > Hi Eric, > > Still trying to get better performance with splice, I noticed that when using splice there are twice the file size memcpy (placed a counter in memcpy), I verified it via samba file transfer and splice-fromnet/out. > > I also used the splice-fromnet/out and using ftrace I did notice that data is copied twice using these routines: skb_splice_bits, pipe_to_file. I'm not sure you're using optimal NIC for splice, which should use skbs with almost all data paged (non-linear), like niu or myri10ge. Jarek P.