Parallel Computer Architecture

8.5 Memory-Based Directory

Protocols:

The SGI Origin System

621

Barnes-Hut: 16-K bodies

Barnes-Hut: 512-K bodies

Ocean:

n = 514

Ocean:

n s 1,026

Radix: 1-M keys

Radix: 4-M keys

LU:

n = 2,048

LU:

n â 4,096

Raytrace: balls

Raytrace: car

Radiosity: room

Radiosity: largeroom

13 5 7 9 1113 151719 2123

25 27 29

31

Number of processors

* I I I

1

I I I I I I I I I II I I

1

I I I I I I I

13 5 7 9 1113151719 212325

27 29

31

Number of processors

FIGURE 8.22 Speedups for the parallel applications on the Origin2000. Two problem sizes are

shown for each application. The Radix sorting program does not scale

well,

and the Radiosity applica-

tion is limited