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From: "Michael S. Tsirkin" <mst@redhat.com>
To: Avi Kivity <avi@scylladb.com>
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X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] Having troubles binding an SR-IOV VF to
 uio_pci_generic on Amazon instance
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On Thu, Oct 01, 2015 at 12:22:46PM +0300, Avi Kivity wrote:
> It's easy to claim that
> a solution is around the corner, only no one was looking for it, but the
> reality is that kernel bypass has been a solution for years for high
> performance users,

I never said that it's trivial.

It's probably a lot of work. It's definitely more work than just abusing
sysfs.

But it looks like a write system call into an eventfd is about 1.5
microseconds on my laptop. Even with a system call per packet, system
call overhead is not what makes DPDK drivers outperform Linux ones.

-- 
MST