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

SXDRAM Configuration

The operating system includes a driver for reserving and managing physically contiguous memory. The memory should be reserved as part of the boot process, because it is likely to be the least fragmented at this time, and chances of finding large blocks of physically contiguous memory are higher during boot time.

The amount of SXDRAM to reserve can be specified by using the sxconfig(1M) command. sxconfig can be executed only by a process with superuser privileges. Here are some examples of sxconfig command use.

To disable fragmentation, enter:

# sxconfig -n

To restore all configuration parameters to the default values, enter:

# sxconfig -d

By default, 0 MBytes of physically contiguous memory is reserved, fragmentation is not allowed, and 32 MBytes of memory is reserved for system use.

To display the current configuration parameters in the driver configuration file, enter:

# sxconfig -c

If the system was not booted after the last time the configuration parameters were changed, then the displayed values will not reflect the actual system set-up. For more information about using sxconfig, refer to the on-line man page.

The sxconfig command resides in the directory /platform/SUNW,SPARCstation-10,SX/sbin; the shell environment variable PATH must include this directory. To find out whether the PATH environment variable includes the /platform/SUNW,SPARCstation-10,SX/sbin directory, type

# echo $PATH


Your search path will be displayed. An example:


If the line displayed does not include /platform/SUNW,SPARCstation-10,SX/sbin, enter the following if you are in either the Bourne shell or the Korn shell:

# PATH=$PATH:/platform/SUNW,SPARCstation-10,SX/sbin export PATH

followed by:

# export PATH

if you are in the Bourne shell.

If you are in the C shell, enter:

# setenv PATH "$PATH /platform/SUNW,SPARCstation-10,SX/sbin"

If 16 MBytes of memory must be reserved, enter:

# sxconfig -s 16

On a system configured with 16 MByte DSIMMs, the maximum amount of SXDRAM that can be reserved in a single block is 16 MBytes. On such systems, when more than 16 MBytes of memory must be reserved for SXDRAM, the sxconfig command can be used to specify that fragmented reservation of the requested amount of SXDRAM is allowed. For example, to reserve 32 MBytes of memory on a system configured with 16 MBytes, enter:

# sxconfig -s 32 -f

sxconfig and reboot causes a search of the system page pool for a contiguous block of memory of the specified size. If the block of memory is found, it is reserved. If fragmentation is specified (as shown above), more than 16 MBytes is specified, and the search fails, the operating system searches for contiguous blocks of 16 MBytes. If no blocks of this size are found, the operating system searches for contiguous blocks of 256 KBytes.

When the SXDRAM configuration is finished, halt the system:

# halt

The Open Boot PROM prompt is displayed on the console:


Boot the system by entering:

ok boot disk -rv

The -r option specifies a reconfiguration boot. The -v option specifies verbose mode. As part of the boot process, the requested amount of SXDRAM will be reserved. Refer to Appendix A, Boot Messages for a listing of the messages that will be displayed.

After the system is rebooted, log in, start OpenWindows, and start the XGL application of your choice.