Shared Memory Usage With 3D Graphics - HP b2600 Administration Manual

For example:
Screen /dev/crt/
ScreenOptions
EnableIncludeInferiorsFix
This gives a system administrator control over when the fix is active and when it is not. In this way, each
site can evaluate whether or not it is beneficial to enable this fix.

Shared Memory Usage With 3D Graphics

Graphics processes use shared memory to access data pertaining to the display device and X11 resources
created by the server. ("Resources" includes windows, colormaps, and cursors.) The X11 server initiates
an independent process called the Graphics Resource Manager (GRM) to manage these resources among
graphics processes. Graphics processes include PEXlib, PHIGS, and Starbase applications. One problem
encountered with GRM shared memory is that it may not be large enough to run some applications.
Graphics applications that require VM double-buffering use large amounts of shared memory. Shared
memory can be completely consumed by several double-buffered graphics windows. When an
application attempts to use more shared memory than is available, the application encounters errors and
might terminate.
You can circumvent the problem by using Server Options to change the shared memory size.
Changing Graphics Shared Memory Size
The size of the shared memory segment used by the GRM can be controlled through a Server Option.
The default value is 0x580000 (5.5 Mbytes) on Series 700 computers.
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Note: The actual GRM shared memory size on a system can be determined by running "ipcs -ma",
finding the entry with CPID matching the process ID of the grmd process and then checking the segment
size (SEGSZ) field.
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If more shared memory space is needed, graphics shared memory size can be increased. For example, to
set it to eight megabytes:
ServerOptions
GraphicsSharedMemorySize=0x800000
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Note: The value must be in hexadecimal. The new value won't take effect until you restart the X Server.
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Graphics Administration Guide for HP-UX 10.20