From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Westphal Subject: Re: [net-next PATCH 1/3] net: make default tx_queue_len configurable Date: Wed, 29 Jul 2015 23:06:18 +0200 Message-ID: <20150729210618.GF32705@breakpoint.cc> References: <1438203103-27013-1-git-send-email-phil@nwl.cc> <1438203103-27013-2-git-send-email-phil@nwl.cc> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, Jesper Dangaard Brouer , Cong Wang , Eric Dumazet , David Miller To: Phil Sutter Return-path: Received: from Chamillionaire.breakpoint.cc ([80.244.247.6]:56091 "EHLO Chamillionaire.breakpoint.cc" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750803AbbG2VGW (ORCPT ); Wed, 29 Jul 2015 17:06:22 -0400 Content-Disposition: inline In-Reply-To: <1438203103-27013-2-git-send-email-phil@nwl.cc> Sender: netdev-owner@vger.kernel.org List-ID: Phil Sutter wrote: > Signed-off-by: Phil Sutter > --- > net/Kconfig | 12 ++++++++++++ > net/ethernet/eth.c | 2 +- > 2 files changed, 13 insertions(+), 1 deletion(-) > > diff --git a/net/Kconfig b/net/Kconfig > index 7021c1b..21c164f 100644 > --- a/net/Kconfig > +++ b/net/Kconfig > @@ -48,6 +48,18 @@ config COMPAT_NETLINK_MESSAGES > config NET_INGRESS > bool > > +config DEFAULT_TX_QUEUE_LEN > + prompt "Default TX queue length (in packets)" if EXPERT > + int > + default 1000 # Ethernet wants good queues > + help > + Set the default value of tx_queue_len for newly created network > + interfaces. It is used by queueing disciplines to determine how many > + packets to keep in backlog before starting to drop new ones. > + > + The default value of 1000 packets is there for a very long time and > + in combination with GSO way too big. > + I can't see how this could be used in a meaningful way. No distro is going to touch this. I don't think sysctl value would help either.