Platform Notes: SPARCstation 10SX and SPARCstation 20 System Configuration Guide

When to Reserve SXDRAM

Caution - Caution -

The memory reserved for SXDRAM will not be available for system use. When reserving SXDRAM, consider the amount of memory left for system use. Ensure that there is sufficient memory left for system use that system performance is not adversely affected.

Reserving SXDRAM can improve the performance of an application that uses the foundation library XGL.

The default configuration is to use no SXDRAM XGL uses SXDRAM for Z buffers and double-buffering. Typically, 8 MBytes of SXDRAM must be reserved if both Z-buffering and double-buffering are used. 4 MBytes must be reserved when Z-buffering is used or when double-buffering is used alone.

For image rotation operations, the amount of SXDRAM that must be reserved should be the same as the size of the image, rounded up to the nearest integer multiple of 1 MByte. For example, a 1200 x 1200 image with four 8-bit channels per pixel will fit in 5.493 MBytes, requiring 6 MBytes of SXDRAM.