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Accelerating SDN/NFV with transparent offloading architecture

*NTT Microsystem Integration Laboratories, Japan †NTT Network Service Systems Laboratories, Japan

Open Networking Summit, Mar. 3-5, 2014, Santa Clara, CA, USA

Koji Yamazaki*, Takeshi Osaka†, Sadayuki Yasuda*, Shoko Ohteru*

and Akihiko Miyazaki*

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Outline

• Challenge

• Our approach

• Experimental results

• Conclusion

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Challenge

How can we enhance the performance of virtual network functions without increasing CAPEX or OPEX?

• Background

Lots of COTS accelerators and SDKs (FPGAs, NPUs, and GPUs)

Framework for saving energy in future networks (ITU-T Y.3021)

• Two objectives

To reduce programming effort

To enable high-performance, energy-efficient operations

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Our approach

Goal: To accelerate required functions easily and efficiently

*ASIP: Application Specific Instruction-set Processor

1. Transparent offloading architecture

New programmable accelerator (ASIP*)

Harmonization among x86 environments

2. Design of application-specific instruction set

Optimal instructions for coarse DPI

Implementation of simple data structure (Bloom filter)

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Overview of ASIP architecture

ALU

MUX

ALU

GPR

MUX

Load/Store

SRAM GPIO

Writeback

Decode

Execute

State Register

Fetch

Memory Access

SDRAM

*ISA: Instruction Set Architecture

Extension

• Embedded RISC CPUs - MIPS - Cadence - Synopsys, etc.

• Tunable architecture

• ISA* extension with tailored compiler allowed

• Customize HW resources

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ASIP for packet stream processing

ALU

MUX

ALU

GPR

MUX

Load/Store

SRAM GPIO

Writeback

Decode

Execute

State Register

Fetch

Memory Access

SDRAM

Configure fast U-plane

FIFO

Ingress Stream FIFO

Egress Stream

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Transparent offloading

C-plane configuration

x86 ASIP

PCIe PCIe

RAM

Core

I-RAM

D-RAM

DMAC

DMA Transfers

Issue DMA instructions

Concept: Control ASIP functions from x86 environment

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Transparent offloading

x86 ASIP

PCIe PCIe

RAM

Core

I-RAM

D-RAM

I-RAM

DMAC

Memory map

DMA Transfers

Search ASIP section

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Transparent offloading

x86 ASIP

PCIe PCIe

RAM

Core

I-RAM

D-RAM

I-RAM I-RAM

Forward functions

DMAC

Memory map

DMA Transfers

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Invoke coarse DPI function

x86 ASIP

PCIe PCIe

RAM

Core

I-RAM

D-RAM

I-RAM I-RAM

Forward functions

DMAC

Memory map

DMA Transfers

... // Test data #define QUEUE_CHECK 50000 ...

int main() { ... // scan 50000 packets loop = 0; do {

bloom_scan(); loop++; } while (loop<QUEUE_CHECK); bloom_destroy(); return EXIT_SUCCESS; }

main()

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Invoke coarse DPI function

x86 ASIP

PCIe PCIe

RAM

Core

I-RAM

D-RAM

I-RAM I-RAM

Forward functions

DMAC

Memory map

DMA Transfers ... …

void bloom_scan() { // Invoke instructions as intrinsics

if (queue_vacancy_check()) {

pop_queue(); sax_hash_match(); sdbm_hash_match(); bernstein_hash_match(); forward_data(); } }

bloom_scan()

22 instructions and 14 registers were added for coarse DPI

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Disassembly of bloom filter matching

x86 ASIP

PCIe PCIe

RAM

Core

I-RAM

D-RAM

I-RAM I-RAM

Forward functions

DMAC

Memory map

DMA Transfers

# of

cycles Profiled disassembly

3 entry a1, 32 1 queue_vacancy_check a2

2 beqz.n a2, 60000465 <bloom_scan+0x19>

1 pop_queue 2 sdbm_hash_match 1 bernstein_hash_match 1 sax_hash_match 1 forward_data

1 retw.n bloom_scan+0x19

0 retw.n

13 cycles per one bloom_scan()

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Experimental results

Evaluation items w/o acceleration w/ our instructions

Run-time

(mean # of cycles)

*50000 packets,

64-bit fixed field,

45-nm sim library.

hash(sax) 116 1

hash(sdbm) 115 2

hash(bernstein) 98 1

bloom_scan 678 13

Hardware size

(logic gate count) core and SRAM 75 KGates 79 KGates

Power dissipation

(mW) core and SRAM < 100 mW < 100 mW

Performance

(64 bytes)

pps (packets/s) 1 Mpps 57 Mpps

bps (bits/s) 723 Mbps 38 Gbps

Down 98%

Extremely low power

50x faster

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Conclusion

Designing an optimal-instruction-set that harmonizes x86 environments

will reduce the costs required for acceleration

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More challenging issues

Proprietary architecture White box architecture

Can open ISA transform the ecosystem of accelerators?

My assumption: Common, open ISA-based APIs reduce further programming costs.

Intel’s AVX ISA Extension Berkeley RISC-V open ISA

Emerging trends of open source SDKs (i.e. Centec’s Lantern)

Accelerators have “the Force” Dark side Light side

Other black box SDKs of COTS (ASSPs, NPUs)

Thank you! Questions?