Re: new ipdelay= option for faster netboot

David Miller
2009-08-18T01:03:13Z

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: