From: Gleb Natapov <gleb@redhat.com>
To: Victor fernandez <Victormanuel.fernandez@usc.es>
Cc: kvm@vger.kernel.org
Subject: Re: Lost of performance over AMD-V with KVM?
Date: Tue, 9 Jul 2013 16:33:40 +0300 [thread overview]
Message-ID: <20130709133340.GA24941@redhat.com> (raw)
In-Reply-To: <51DC001B.2010703@usc.es>
On Tue, Jul 09, 2013 at 02:20:43PM +0200, Victor fernandez wrote:
> Hi EveryBody!
>
> recently, we have tested some specific High Energy Physics benchmarks that
> was running over S.L.6 and we observed that the performance over AMD
> machines was really bad, about 30-40% lost. We were investigating
> and we conclude that the problem was with some cpu flags. These cpu
> flags are important for running our application because it is optimazed
> for running with them. So, we tuning our KVM with the name of flags
> parameters and with "-cpu host" parameter too, but
> we observed that the flags that we needed, they weren't included when
> we started the S.L.6 instance. We try to solve it, but when we conclude
> that the specific flags weren't included in the code of the last
> versions of KVM
> and LibVirt(capabilities). Do you know something about this problem or
> you are aware of this?
>
What flags are missing?
--
Gleb.
next prev parent reply other threads:[~2013-07-09 13:33 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-09 12:20 Lost of performance over AMD-V with KVM? Victor fernandez
2013-07-09 13:33 ` Gleb Natapov [this message]
[not found] ` <51DC1EC4.4000001@usc.es>
2013-07-09 14:47 ` Gleb Natapov
[not found] ` <51DC24C9.8080700@usc.es>
2013-07-09 15:00 ` Gleb Natapov
[not found] ` <51DC274D.8090409@usc.es>
2013-07-09 15:16 ` Gleb Natapov
[not found] ` <51DC2C92.4020605@usc.es>
2013-07-09 16:08 ` Gleb Natapov
2013-07-11 12:52 ` Victor fernandez
2013-07-11 14:07 ` Gleb Natapov
[not found] ` <51DEC106.4040300@usc.es>
2013-07-11 14:43 ` Gleb Natapov
2013-07-09 15:17 ` Victor fernandez
2013-07-09 14:42 ` Victor fernandez
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