From: Avi Kivity <avi@redhat.com>
To: Drew Johnson <drewtomjohnson@gmail.com>
Cc: kvm@vger.kernel.org
Subject: Re: Guest virtual CPUs limited to only 50% of host CPU
Date: Tue, 05 Apr 2011 12:03:39 +0300 [thread overview]
Message-ID: <4D9ADAEB.1030301@redhat.com> (raw)
In-Reply-To: <AANLkTikMRv-agWtNHsUt9jEBssRr4mMO-pP_Uo4KT1YS@mail.gmail.com>
On 03/31/2011 11:03 PM, Drew Johnson wrote:
> Hi,
>
> I am using Qemu-KVM-0.12.5
This is somewhat old. Try upgrading.
> on Intel Xeon (Vt-x enabled) processors and
> monitoring the system using htop on the host. On the processors that
> are running Qemu-KVM I am seeing a 50/50 split between userspace and
> guest ("gu:" in htop). I have pinned the vCPU qemu-kvm threads to
> specific host CPUs using taskset. In the guest the CPUs are nearly
> 100% userspace in htop.
>
> Does anyone have ideas on why this is? Is there a way I can get much
> higher utilization for the guest virtual CPUs wrt the host?
>
Please build qemu with --disable-cpu-strip and run 'perf top' to see
what's going on.
--
error compiling committee.c: too many arguments to function
next prev parent reply other threads:[~2011-04-05 9:03 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-31 21:03 Guest virtual CPUs limited to only 50% of host CPU Drew Johnson
2011-04-05 9:03 ` Avi Kivity [this message]
2011-04-29 0:30 ` Drew Johnson
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