From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [net-next rfc 1/3] net: avoid high order memory allocation for
 queues by using flex array
Date: Wed, 19 Jun 2013 23:05:12 -0700
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To: Jason Wang <jasowang@redhat.com>
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On Thu, 2013-06-20 at 13:14 +0800, Jason Wang wrote:

> A drawback of NETIF_F_LLTX is that we may contend on qdisc lock
> especially when we have a huge number of tx queues.

For your information loopback driver is LLTX, and there is no qdisc on
it, unless you specifically add one.

Once you add a qdisc on a device, you hit the typical contention on a
spinlock. But its hard to design a parallel qdisc. So far nobody did
that.