4.3.10 virtio bridged networking performance

[Chris Brown]

virtio with 4.3.10 is totally unusable. This is observed on all host types and different hardware configurations.

Simple Test case: Load an EL or OEL 6.x guest and configure it with a bridged virtio nic. Perform a simple network operation in the guest such making/removing a directory and some files on NFS v3 mounted filesystem in the guest.

EG:

mkdir foobar
time { for i in `seq 0 1000`; do echo foo > foobar/file_${i}; done }
time rm -rf foobar

Windows Host Example

• Windows 7 Dual Intel x5570 CPU 48Gb Ram 10K SAS disks
• SL 6.5 Guest 2 vcpu 4GB RAM 20GB vdi
• With virtio:
  • create

    real: 1m10.749s
    user: 0m0.151s
    system: 0m0.607s
    

  • remove

    real: 0m39.892s
    user: 0m0.000s
    system: 0m0.418s
    

• With 82545EM:
  • create

    real: 0m2.616s
    user: 0m0.119s
    system: 0m0.646s
    

  • remove

    real: 0m1.746s
    user: 0m0.002s
    system: 0m0.540s
    

OEL 6.5 Host Example

• OEL 6.5. Dual Intel e5540 CPU 73Gb Ram 10K SAS disks
• SL 6.5 Guest 2 vcpu 4GB RAM 20GB vdi
• With virtio:
  • create

    real: 1m1.833s
    user: 0m0.131s
    system: 0m0.402s
    

  • remove

    real: 0m31.232s
    user: 0m0.001s
    system: 0m0.401s
    

• With 82545EM:
  • create

    real: 0m2.100s
    user: 0m0.112s
    system: 0m0.623s
    

  • remove

    real: 0m0.931s
    user: 0m0.001s
    system: 0m0.311s