Maryam Tahhan and Kevin Traynor Intel Accelerating the Path to the Guest

Maryam Tahhan and Kevin Traynor

Intel

Accelerating the Path to the Guest

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TRANSFORMING NETWORKING & STORAGE

Legal Disclaimers

Intel processor numbers are not a measure of performance. Processor numbers differentiate features within each processor family, not across different processor families: Go to: Learn About Intel® Processor Numbers

Intel, the Intel logo and Xeon are trademarks of Intel Corporation in the U.S. and/or other countries.

*Other names and brands may be claimed as the property of others.

Copyright © 2014 Intel Corporation. All rights reserved

Intel Confidential

http://www.intel.com/products/processor_number

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Agenda

• NFV• Guest access methods• Summary• Q&A

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Network Function Virtualization (NFV)

By 2017 mobile traffic will have grown 13x in the space of 5 years.*

In 2017 there will be 3x more connected devices than people on earth.*

Service Providers are moving to virtualize the functionality of network components in an effort to move away from custom ASICs, and operate on standard servers.

The network functions running on a guest require near native performance.

* http://www.intel.com/content/www/us/en/communications/internet-minute-infographic.html

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Legacy virtio-net

• virtio-net is a para-virtualized network driver based on virtio.

• A guest with a virtio_net driver, shares a number of virtqueues with QEMU.

• The mechanism by which traffic is passed is comprised of two parts: • The datapath.

• The notification path.

Guest

QEMU

Operating System

Virtio DriverTX

RX

Kernel Space

OVS Datapath

Tap

KVM

1 2

Eth X1

2

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Intel® Data Plane Development Kit and ivshmem

• Physically contiguous memory

• 1GB pages• /dev/hugepages/

rte_map0

Hugepages

• Lockless• Efficient for IPC• Rx/Tx pairs

Rings

• aka Nahanni*• QEMU* 1.4.0• Host Initiated

ivshmem

• Command line• hugepage location• ivshmem device

QEMUPatch

Intel® DPDK ivshmem

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Shared MemoryMemory

QEMUOperating System

ivshmem

RX

TX

Kernel Space

OVS Datapath

DPDK Ring API

DPDK PMD

OVS client

DPDK Ring API

1GB

PCI dev (04:00.0)

BAR2

mempool

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Intel® DPDK rings and ivshmem Characteristics

• Upstream Patch• MaintenanceQEMU

• Regions of memory• Security groups Security

• Modifications needed• Difficult

Live migration

Current Future• Zero copy• Fast performance

Performance

• Guests can access host memory

• Unsuitable for untrusted guests

Security

• Host initiated sharing• Shared at guest start up

Live Migration

• DPDK Guest applicationCompatibility

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VhostNetQEMU

Operating System

Virtio Driver

RX

TX

Kernel Space

OVS Datapath

Tap KVM

1 2

Eth X

ioeventfd

irqfd

vhost-net

us-vhostQEMU

Operating System

Virtio DriverRX

TX

Kernel Space

OVS Datapath

DPDK vhost

KVM

1

2

DPDK x

eventfd

linkioeventfd

CUSE

irqfd

IOCTL

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us-vhost Characteristics

• zero copy• Merge-able buffersPerformance

• virtio-net backend enhancementsFeatures

• Library provided by DPDKus-vhost Library

• vhost-user QEMU

Current Future• Less copies and

context switches.Performan

ce

• Virtqueues mapped to vswitchd address space.

Security

• Solution exists.Live Migration

• DPDK guest application

• Virtio-net

Compatibility

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Use Case Comparison

Use Case 1Highest

performance

Trusted Guests

DPDK VNF

No live migration

Use Case 2Accelerated performanc

e

Untrusted Guests

DPDK & Virtio-net

VNFs

Live migration

dpdkr & ivshmem

us-vhost

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Summary

NFV requires high bandwidth, low latency interfaces into the Network Function Virtualisation Infrastructure

2 accelerated paths to the guest recently enabled in netdev-dpdk

Trade off between performance, security, live migration and compatibility

DPDK has an active community supporting it

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TRANSFORMING NETWORKING & STORAGETRANSITIONING NETWORKING & STORAGE

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Q & A

Documents

Maryam Tahhan and Kevin Traynor Intel Accelerating the Path to the Guest