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Date: Fri, 28 Oct 2016 09:25:25 -0700
From: Stephen Hemminger <stephen@networkplumber.org>
To: Ferruh Yigit <ferruh.yigit@intel.com>
Message-ID: <20161028092525.696652d4@xeon-e3>
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Cc: DPDK <dev@dpdk.org>
Subject: Re: [dpdk-dev] KNI discussion in userspace event
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On Fri, 28 Oct 2016 15:31:50 +0100
Ferruh Yigit <ferruh.yigit@intel.com> wrote:

> Discussed alternatives were:
> * Tun/Tap
> This won't be as fast as KNI and performance is an issue.


That is a myth. Both require the some number of copies.
TUN/TAP copies is a syscall and KNI copies is a kthread.
Actually, the KNI method is worse because it has kernel thread
always running chewing a CPU. I.e it is pure poll mode.