Operating System Support for Multiprocessor Systems-on-Chip

(1)

Institute for Information Processing Technology (ITIV)

Prof. Dr.-Ing. K. D. Müller-Glaser · Prof. Dr.-Ing. J. Becker · Prof. Dr. rer. nat. W. Stork

Operating System Support for

Multiprocessor Systems-on-Chip

(2)

Agenda

1. Introduction

2. Adaptive System + Shop Architecture

3. Preliminary Results

(3)

I

NTRODUCTION

Network Processing Unit

RISC Power Managem. Router RAM

EASI

LY

SCAL

ABL

E

HOMOGENEOUS PLATFORM DISTRIBUTED MEMORY HETEROGENEOUS PLATFORMS SHARED MEMORY Video Accelerator Audio Accelerator Memory

CPU _ManagementPower

Bridge USB UART Bluetooth Webcam GPIO

HAR

DLY

SCAL

ABL

E

HOMOGENEOUS / HETEROGENEOUS PLATFORMS

Homogeneous

Heterogeneous

Performance

Power

Flexibility

Programmability

ADAPTATION

(4)

A

RCHITECTURES IN THE MARKET

(5)

Context

Telecom Multimedia

Domain-specific

… CPU DSP DSP RAM I/O OS Telecom Multi média

• Centralized control (GPP)

• Specialized ISPs, ASIPs

• Static task mapping

• Bus-like interconnect

Homogeneous Adaptive Distributed Heterogeneous Static Centralized Homogeneous Dynamic Centralized

• Centralized control (OS)

• Symmetric multicore

• D

ynamic load balancing

• High-freq. memory & Bus

• Array of tiny scalar ISP w. private RAM

• Interconnected through a NoC

• Adaptive

• DVFS

• Dynamic Task Mapping

(6)

S

HOP

Self-adaptive Homogeneous Platform

Network Processing Unit

NPU

RISC Power Management Router RAM

Task N

...

Task 2

Task 1

RTOS

Distributed Memory Message Passing (State of the art)

Task Migration

Frequency Scaling

2 1 3 4

(7)

S

HOP OS

Operating System

1

2 Features:

NPU

Task

Ports

3

4

192.168.1.3

4 1000, 1001

192.168.1.2

3 1000

Step 1: Registering Tasks

192.168.1.1

2 1000

1001

1 Step 2: Requesting Task Location

Step 3: Receiving Task Location

192.168.1.3

4 1000, 1001

Step 4: Establishing the Link

Tiny, preemptive OS with dynamic loader

Scheduler based on thread priorities

Communication between local and remote threads

Use of RAW/UDP/TCP IP connection to ensure

reliable communication

Possible use of a self-adaptive RAW/UDP/TCP IP

protocol

Frequency scaling

DMA support

(8)

S

HOP OS

Operating System

1

4 NPU

Task

Ports

192.168.1.3

4 1000, 1001

192.168.1.2

3 1000

Step 1: T4 is selected to be migrated

192.168.1.1

2 1000

1001

1 Step 4: Sending information to the master node

Step 5: Removing T4 entry from routing table

Step 6: Migrating T4 to NPU 192.168.2.3

Routing Table (Master node)

3

2 Task Migration

Step 7: Sending new position to the master node

Step 8: Registering T4 in the routing table

192.168.2.3

4 1000, 1001

Step 2: Sending information to the sender tasks

Step 3: Stopping sending packets to T4

(9)

S

HOP OS

Operating System

1

2 RAW/UDP/TCP protocol

Fault

Packet Lost

Protocol Speed QoS

Raw High No

UDP/IP Medium No TCP/IP Low Yes

(10)

S

HOP

OS

software

Applications

software

Processor

hardware

Router

hardware

FPGA

SystemC

(11)

Platforms for validation

(12)

Platforms for validation

(13)

M

ETRICS AND VALIDATION FLOW

PROFILING

APPLICATION

SPLITTING

ANSI C CODE

PROCESSING REQUIREMENTS

SNAPSHOT

TASK GRAPH WITH

PROCESSING COST

ANSI C CODE + API

SPLIT APPLICATION

PERFORMANCE MEASUREMENT

NEW

STATIC

MAPPING

INITIAL

STATIC

MAPPING

ANSI C CODE

+ API

SPLIT APPLICATION

PERFORMANCE MEASUREMENT

NEW

DYNAMIC

MAPPING

INITIAL

STATIC

MAPPING

ANSI C CODE

+ API

PERFORMANCE SMi

_{PERFORMANCE DMI}

(14)

SYSTEM

A

DAPTIVE SYSTEM

Diagnosis

O = f(l)

Action

Monitoring

The user feeds the

O=f(l) law, the system then

handles decision (action)

making accordingly

(15)

H

OW TO MANAGE ADAPTABILITY?

Events and Maps

Events represent perturbations

-

decisions taken based on history

-

stored in DRET: Distributed Raw Event Table

The set of all tiles states represents the map of the MPSoC

-

temperature map

-

power consumption map

-

working/not working map

Maps are stored in AIM: Architecture Instant Map

MONITORING INSTRUMENTED SYSTEM SENSORS

DRET

DIAGNOSIS

AIM

ONLINE APPLICATION REMAPPING OAR SENSORS DRET DIAGNOSIS

OAR

AIM

LEVEL 1

LEVEL 2

LEVEL 3

Three levels of reactiveness

(16)

H

OW TO MANAGE ADAPTABILITY?

CLUSTER 4 CLUSTER 3 CLUSTER 2 Diagnosis OAR AIM Diagnosis OAR Diagnosis OAR Diagnosis OAR Diagnosis OAR AIM Diagnosis OAR Diagnosis OAR Diagnosis OAR Diagnosis OAR AIM Diagnosis OAR Diagnosis OAR Diagnosis OAR Diagnosis OAR AIM Diagnosis OAR Diagnosis OAR Diagnosis OAR CLUSTER 1

(17)

D

RET

Create Table Dump Table Rows Columns Clock

cycles Rows Columns cyclesClock

1 1 2041 1 1 49713

2 2 2357 2 2 96322

3 3 3018 3 3 158583

4 4 3633 4 4 235715

5 5 4270 5 5 328199

Insert Get First Row Rows Columns Clock

1 1 107 1 1 43

1 2 173 2 1 52

1 3 193 3 1 61

1 4 214 4 1 70

1 5 236 5 1 79

Sort Table Delete Table Rows Columns Clock

1 1 447 1 1 1401

2 2 459 2 2 1941

3 3 471 3 3 2645

4 4 483 4 4 3178

5 5 495 5 5 3830

DISTRIBUTED RAW EVENT TABLE

0 1250 2500 3750 5000 1 2 3 4 5 2041 2357 3018 3633 4270 Create Table 0 75 150 225 300 1 2 3 4 5 107 173 193 214 236 Insert

(18)

E

XPERIMENTS

MONITORING

Diagnosis O = f(l) Action Monitoring

• CPU WORKLOAD

• FIFO USAGE

• FREQUENCY

ACTUAL

• TEMPERATURE

• NOC USAGE

FUTURE

(19)

DIAGNOSIS

20

21

22

23

24

19

17

15

10

11

12

13

14

9

7

5

0

1

2

3

4

18

16

8

6 S

W

N

E

S

W

N

E

S

W

N

E

S

W

N

E

Diagnosis O = f(l) Action Monitoring

E

XPERIMENTS

(20)

E

XPERIMENTS

CASE STUDY (MJPEG DECODER)

Sender T1 IVLC T2 IQUANT T3 IDCT T4

3

2

0

1 T1

T3

T2

T4

PROFILING APPLICATION SPLITTING ANSI C CODE

PROCESSING REQUIREMENTS SNAPSHOT

TASK GRAPH WITH PROCESSING COST

ANSI C CODE + API

(21)

ACTION

5 10 15 20 25 30 35 40 45 0 10 20 30 40 50 60 70 80 TIME (ms) NUMBER OF PACKETS

MJPEG MULTI−TASK PROCESSOR (600MHz)

BUFFER FILLING MIGRATION COST 10 15 20 25 30 35 40 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 TIME (ms) THROUGHPUT (MB/s)

DYNAMIC MAPPING MIGRATION TRIGGER MIGRATION POINT 0 8 16 24 32 40 48 56 64 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 x 106 TASK SIZE (KB)

MIGRATION TIME (CLOCK CYCLES)

0 5 10 15 20 25 30 35 40 45 50 0.5 1 1.5 2 2.5 3 3.5 4 4.5 TIME (ms) Throughput (MB/s)

0 5 10 15 20 25 30 35 40 45 500 10 20 30 40 50 60 70 80

FIFO Filling (Number of Positions)

DYNAMIC MAPPING MIGRATION COST Action Diagnosis O = f(l) Monitoring 3 2 1 3 ₂ 3 2 1 3