From: David Miller <davem@davemloft.net>
To: tim.bird@am.sony.com
Cc: r.schwebel@pengutronix.de, vda.linux@googlemail.com,
linux-kernel@vger.kernel.org, linux-embedded@vger.kernel.org,
arjan@linux.intel.com, kernel@pengutronix.de,
netdev@vger.kernel.org
Subject: Re: new ipdelay= option for faster netboot
Date: Mon, 17 Aug 2009 18:03:23 -0700 (PDT) [thread overview]
Message-ID: <20090817.180323.253692704.davem@davemloft.net> (raw)
In-Reply-To: <4A89DB15.6060101@am.sony.com>
From: Tim Bird <tim.bird@am.sony.com>
Date: Mon, 17 Aug 2009 15:35:01 -0700
> Tim Bird wrote:
>> See the definitions of CONF_PRE_OPEN and CON_POST_OPEN
>> in net/ipv4/ipconfig.c
>>
>> They are set to ridiculously long values. In my experience,
>> you can cut them down considerably with no dangerous side
>> effects (but I haven't asked the network guys about the
>> possible downsides).
>
> It turns out that others have seen this delay. Simon
> Arlott recently posted a patch to make the delay avoidable
> at boot time from the kernel command line.
>
> See http://patchwork.kernel.org/patch/31678/
"Rediculiously long" is a relative term.
I have card/switch combinations that take up to 10 seconds to
negotiate a proper link.
So what's there now is actually a quite agressive setting.
And BTW, discussions about stuff like this belong on
netdev@vger.kernel.org, which has been added to the CC:
next parent reply other threads:[~2009-08-18 1:03 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20090814204305.GA31727@pengutronix.de>
[not found] ` <4A89AC40.2040109@am.sony.com>
[not found] ` <4A89DB15.6060101@am.sony.com>
2009-08-18 1:03 ` David Miller [this message]
2009-08-18 1:24 ` new ipdelay= option for faster netboot Tim Bird
2009-08-18 1:27 ` David Miller
2009-08-18 1:40 ` Tim Bird
2009-08-18 1:56 ` David Miller
2009-08-19 11:57 ` Jamie Lokier
2009-08-18 4:56 ` Denys Vlasenko
2009-08-18 5:00 ` David Miller
2009-08-18 1:31 ` Rick Jones
2009-08-18 2:45 ` david
2009-08-18 4:56 ` Willy Tarreau
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