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From: Nadav Har'El <nyh@math.technion.ac.il>
To: Chegu Vinod <chegu_vinod@hp.com>
Cc: kvm@vger.kernel.org
Subject: Re: Networking performance on a KVM Host (with no guests)
Date: Sun, 22 Apr 2012 14:09:04 +0300	[thread overview]
Message-ID: <20120422110904.GA29760@fermat.math.technion.ac.il> (raw)
In-Reply-To: <loom.20120421T022448-352@post.gmane.org>

On Sat, Apr 21, 2012, Chegu Vinod wrote about "Re: Networking performance on a KVM Host (with no guests)":
> some traffic through between the hosts... then we can't expect to get line rate 
> on that private NIC. 

If you're not using device assignment, then just disable intel_iommu.

If you *are* using device assignment, try setting intel_iommu to something
other then on. Maybe intel_iommu=pt will work (see
http://lwn.net/Articles/329174/). But I actually never tried this myself -
so let me know if it works ;-)

Is anyone else aware of a different "best practice", on how to enable
VT-d for device assignment, without any changes (in performance or
security) in the host?

-- 
Nadav Har'El                        |                    Sunday, Apr 22 2012, 
nyh@math.technion.ac.il             |-----------------------------------------
Phone +972-523-790466, ICQ 13349191 |Sign in zoo: Do not feed the animals. If
http://nadav.harel.org.il           |you have food give it to the guard on duty

      reply	other threads:[~2012-04-22 11:09 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-04-19  3:53 Networking performance on a KVM Host (with no guests) Chegu Vinod
2012-04-19  5:43 ` Gleb Natapov
2012-04-19  6:42   ` Jean-Philippe Menil
2012-04-20 14:15   ` Chegu Vinod
2012-04-20 19:35     ` Nadav Har'El
2012-04-21  0:30       ` Chegu Vinod
2012-04-22 11:09         ` Nadav Har'El [this message]

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