Features/Virtx2apic

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(Bump to 100, indicate virt-* should enable this automatically)
 
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== Owner ==
 
== Owner ==
 
* Name: [[User:avik| Avi Kivity]]
 
* Name: [[User:avik| Avi Kivity]]
 
 
* Email: <avi@redhat.com>
 
* Email: <avi@redhat.com>
  
 
== Current status ==
 
== Current status ==
* Targeted release: [[Releases/13]]  
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* Targeted release: [[Releases/13 | Fedora 13]]  
* Last updated: 2010-01-26
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* Last updated: 2010-04-06
* Percentage of completion: 90%
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* Percentage of completion: 100%
  
 
== Detailed Description ==
 
== Detailed Description ==
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== Scope ==
 
== Scope ==
x2apic support is already present in the guest and host.
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* x2apic support is already present in the guest and host.
libvirt/virt-manager = ?
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* libvirt/virt-manager = ?
  
 
== How To Test ==
 
== How To Test ==
Run a Fedora 13 guest on a Fedora 13 host, with x2apic enabled.
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* Run a Fedora 13 guest on a Fedora 13 host, with x2apic enabled. Installs via virt-install and virt-manager should enable this automatically.
 
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* Verify that x2apic is present in /proc/cpuinfo.
Verify that x2apic is present in /proc/cpuinfo.
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* Verify dmesg contains "Enabling x2apic".
Verify dmesg contains "Enabling x2apic".
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* For a bonus, measure the overhead of an IPI with and without x2apic.
 
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For a bonus, measure the overhead of an IPI with and without x2apic.
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== User Experience ==
 
== User Experience ==
 
User experience is unchanged except for improved performance.
 
User experience is unchanged except for improved performance.
 
  
 
== Dependencies ==
 
== Dependencies ==
kernel
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* kernel
qemu-kvm
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* qemu-kvm
libvirt
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* libvirt
virt-manager
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* virt-manager
  
 
== Contingency Plan ==
 
== Contingency Plan ==
Since this is a transparent feature, no contingency plan is necessary.
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* Since this is a transparent feature, no contingency plan is necessary.
  
 
== Documentation ==
 
== Documentation ==
* Nope.
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* '''FIXME''': link to upstream docs?
  
 
== Release Notes ==
 
== Release Notes ==
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== Comments and Discussion ==
 
== Comments and Discussion ==
 
* See [[Talk:Features/Virtx2apic]]
 
* See [[Talk:Features/Virtx2apic]]
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[[Category:FeatureAcceptedF13]]
  
 
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[[Category:Virtualization|Virtx2apic]]
[[Category:FeatureReadyForWrangler]]
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[[Category:F13_Virt_Features|Virtx2apic]]
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<!-- After review, the feature wrangler will move your page to Category:FeatureReadyForFesco... if it still needs more work it will move back to Category:FeaturePageIncomplete-->
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Latest revision as of 22:14, 6 April 2010

Contents

[edit] Virt x2apic

[edit] Summary

x2apic is an x86 feature that improves performance, especially on large systems. Virt x2apic is a port of this feature for KVM, improving guest performance, especially for guests with many virtual processors.

[edit] Owner

[edit] Current status

  • Targeted release: Fedora 13
  • Last updated: 2010-04-06
  • Percentage of completion: 100%

[edit] Detailed Description

x2apic improves guest performance by reducing the overhead of APIC access, which is used to program timers and for issuing inter-processor interrupts. By exposing x2apic to guests, and by enabling the guest to utilize x2apic, we improve guest performance.

[edit] Benefit to Fedora

Fedora users will see improved guest performance and lower cpu utilization.

[edit] Scope

  • x2apic support is already present in the guest and host.
  • libvirt/virt-manager = ?

[edit] How To Test

  • Run a Fedora 13 guest on a Fedora 13 host, with x2apic enabled. Installs via virt-install and virt-manager should enable this automatically.
  • Verify that x2apic is present in /proc/cpuinfo.
  • Verify dmesg contains "Enabling x2apic".
  • For a bonus, measure the overhead of an IPI with and without x2apic.

[edit] User Experience

User experience is unchanged except for improved performance.

[edit] Dependencies

  • kernel
  • qemu-kvm
  • libvirt
  • virt-manager

[edit] Contingency Plan

  • Since this is a transparent feature, no contingency plan is necessary.

[edit] Documentation

  • FIXME: link to upstream docs?

[edit] Release Notes

  • Fedora 13 virtualization supports x2apic in both the host and guest roles.

[edit] Comments and Discussion