From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Marchand <david.marchand@6wind.com>
Subject: Re: [Qemu-devel] Why I advise against using ivshmem
Date: Tue, 17 Jun 2014 11:03:32 +0200
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Cc: Vincent JARDIN <vincent.jardin@6wind.com>,
	Henning Schild <henning.schild@siemens.com>,
	Olivier MATZ <olivier.matz@6wind.com>,
	kvm <kvm@vger.kernel.org>, qemu-devel <qemu-devel@nongnu.org>,
	Linux Virtualization <virtualization@lists.linux-foundation.org>,
	"thomas.monjalon@6wind.com" <thomas.monjalon@6wind.com>
To: Stefan Hajnoczi <stefanha@gmail.com>,
	Paolo Bonzini <pbonzini@redhat.com>
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Hello all,

On 06/17/2014 04:54 AM, Stefan Hajnoczi wrote:
> ivshmem has a performance disadvantage for guest-to-host
> communication.  Since the shared memory is exposed as PCI BARs, the
> guest has to memcpy into the shared memory.
>
> vhost-user can access guest memory directly and avoid the copy inside the guest.

Actually, you can avoid this memory copy using frameworks like DPDK.


> Unless someone steps up and maintains ivshmem, I think it should be
> deprecated and dropped from QEMU.

Then I can maintain ivshmem for QEMU.
If this is ok, I will send a patch for MAINTAINERS file.


-- 
David Marchand