From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH] sky2: skb recycling Date: Tue, 21 Oct 2008 07:54:18 +0200 Message-ID: <48FD6E8A.6060304@cosmosbay.com> References: <20081020190922.7dd6510a@extreme> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Jeff Garzik , netdev@vger.kernel.org To: Stephen Hemminger Return-path: Received: from smtp28.orange.fr ([80.12.242.100]:23173 "EHLO smtp28.orange.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751764AbYJUFyb convert rfc822-to-8bit (ORCPT ); Tue, 21 Oct 2008 01:54:31 -0400 In-Reply-To: <20081020190922.7dd6510a@extreme> Sender: netdev-owner@vger.kernel.org List-ID: Stephen Hemminger a =E9crit : > Add support for recycling tx buffers into receive buffers. > This is experimental at this point. >=20 I really like this skb recycling =46or best performance, driver should perform TX completion before RX c= ompletion, so that freshly added skb in recycle queue have a chance being reused right aft= er. Apparently sky2 tx handling is finegrained (events posted by NIC) But still, this mechanism also use more skbs per device, especially on = dormant ones. If your RX ring has 256 skb, then adding the recycle queue can adds 256= more skbs... One MB or event more... Maybe we should flush the recycle queue, every 5 seconds or so, especia= lly if device is dormant (no RX on it, litle heartbeat TX)