CPU Power vs. Network Bandwidth

An MS Excel workbook or plain ASCII version. Screendumps are also available: DEM compression and textures.

A tradeoff/penalty of using compressed versions of DEM and textures is shown on charts:

• DEM, compression ratio 32, Postscript or gif.
• textures, quality 7, av. compression ratio 18.36, Postscript or gif.
• textures, quality 6, av. compression ratio 48.60, Postscript or gif.

Critical points for different CPUs

A critical point for a certain CPU is a bandwidth, for which the time necessary to download uncompressed version of data and the total time of downloading compressed version and decompressing it are equal. For lower bandwidths compression usage results in total time decreasing, for higher bandwidths it leads to slow-downs.

R10000

• DEM: 2.2 Mb/s
• Textures, quality 7: 3.1 Mb/s
• Textures, quality 6: 2.59 Mb/s

R4400 133MHz

• DEM: 549 kb/s
• Textures, quality 7: 856 kb/s
• Textures, quality 6: 1.15 Mb/s

Pentium 75MHz

• DEM: 380 kb/s
• Textures, quality 7: 590 kb/s
• Textures, quality 6: 749 kb/s