From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Hisham Kotry" Subject: Re: skb diet Date: Sun, 16 Apr 2006 14:56:53 +0200 Message-ID: References: <200604152122.01914.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Cc: netdev@vger.kernel.org Return-path: Received: from pproxy.gmail.com ([64.233.166.178]:52946 "EHLO pproxy.gmail.com") by vger.kernel.org with ESMTP id S1750726AbWDPM4y convert rfc822-to-8bit (ORCPT ); Sun, 16 Apr 2006 08:56:54 -0400 Received: by pproxy.gmail.com with SMTP id i49so442454pye for ; Sun, 16 Apr 2006 05:56:53 -0700 (PDT) To: "Andi Kleen" In-Reply-To: <200604152122.01914.ak@suse.de> Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org > Where would that tag list be stored if you want to remove the > 40 bytes of ->cb? I apologize if I wasn't clear, the tag list would go in a new skb->tags field replacing the existsing skb->cb array, so the skb would lose 40-sizeof(void*) bytes wich seems reasonable to me. > Linux 2.0 did something like this, but that was removed for good > reasons. Now TCP always clones skbs before sending it out. Do you remember what those reasons were? I couldn't find a related discussion in the archives. I think the BSD mbuf tags approach is sound enough to justify the move. > And optimizing for uncommon cases (not TCP) doesn't seem too useful. As pointed out by Bert Hubert, there are people who have heavy traffic on non-tcp connections. Thanks, Hisham