Re: [PATCH] Disable TSO for non standard qdiscs

[Stephen Hemminger <shemminger@linux-foundation.org>]

On Thu, 31 Jan 2008 13:46:32 +0100
Andi Kleen <andi@firstfloor.org> wrote:

> 
> TSO interacts badly with many queueing disciplines because they rely on 
> reordering packets from different streams and the large TSO packets can 
> make this difficult. This patch disables TSO for sockets that send over 
> devices with non standard queueing disciplines. That's anything but noop 
> or pfifo_fast and pfifo right now.
> 
> Longer term other queueing disciplines could be checked if they
> are also ok with TSO. If yes they can set the TCQ_F_GSO_OK flag too.
> 
> It is still enabled for the standard pfifo_fast because that will never
> reorder packets with the same type-of-service. This means 99+% of all users
> will still be able to use TSO just fine.
> 
> The status is only set up at socket creation so a shifted route
> will not reenable TSO on a existing socket. I don't think that's a 
> problem though.
> 
> Signed-off-by: Andi Kleen <ak@suse.de>
> 


Fix the broken qdisc instead.

-- 
Stephen Hemminger <stephen.hemminger@vyatta.com>