Re: new ipdelay= option for faster netboot

From: Tim Bird <redacted>
Date: Mon, 17 Aug 2009 15:35:01 -0700

Tim Bird wrote:

quoted

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: