Hier die Beschreibung zu CAT_MEM > 5:


Prior to AIX 4.3.2 the limitation of CAT_MEM=5 has and still exists on
graPHIGS.  In July of this year we modified graPHIGS code to allow the use
of CAT_MEM=8 in CATIA.  This change is available in the AIX 4.3.3 GOLD code
and is also available as a PTF/APAR for AIX 4.3.2.

The necessary AIX 4.3.2 APARs for graPHIGS are: IY02351 & IY03327

In conjunction with the installation of the above APARs, the "catini"
script in the CATIA environment must be modified to NOT limit CAT_MEM to 5
as it does for many levels of CATIA.  I'm not sure in what level of CATIA
this will be changed, but here are the changes required.

Edit /usr/catia/cfg/code/bin/catini or a local copy and modify the section
of that file shown below to look like the section that follows it.

----- OLD -----

                if [ $CAT_MEM -le 8 -a $CAT_MEM -gt 5 ]; then
                        CAT_MEM=5
                        export CAT_MEM
                elif [ $CAT_MEM -lt 0 -o $CAT_MEM -gt 8 ]; then
                        tput clear
                        messag "Invalid CAT_MEM argument : $CAT_MEM" ""
'$CAT_MEM'
                        exit 1
                elif  [ $CAT_MEM -eq 0 ]; then
                        unset CAT_MEM
                fi

----- NEW -----

                if [ $CAT_MEM -lt 0 -o $CAT_MEM -gt 8 ]; then
                        tput clear
                        messag "Invalid CAT_MEM argument : $CAT_MEM" ""
'$CAT_MEM'
                        exit 1
                elif  [ $CAT_MEM -eq 0 ]; then
                        unset CAT_MEM
                fi

----- END -----

OpenGL made a similar change about the same time.
The AIX 4.3.2 APAR for OpenGL is: IY02614

Below, I've included the section of the AIX 4.3.3 /usr/lpp/bos/README that
discusses this new capability for graPHIGS.

-----------------------------------------------------------------------------

graPHIGS Shared Segments
------------------------
With the changes made to the internals of the graphics subsystem, the
number of segments used by the graPHIGS runtime environment is reduced,
providing
more segments for the application and allowing the application to process
larger models.

Here are the specifics.

In AIX versions prior to AIX 4.3.3, for graPHIGS applications that use
Large Program Support (preallocated big data heap), the maximum data
addressability
for thread-safe graPHIGS programs running on a multiprocessor system or
graPHIGS programs running on a uni-processor system was 1.25 GB
(5 segments).  With changes in AIX 4.3.3 these types of programs can now
access up to 2 GB (8 segments) of contiguous memory.

The AIX operating system 32-bit programming environment provides up to 8
contiguous segments (3-10) for use as the big data heap for an application
that wants to use Large Program Support.  (See the AIX General Programming
Concepts manual for additional information on Large Program Support.)
Thus the maximum heap that an application can access when using Large
Program Support is 2 GB.

Graphics adapter I/O (used by graPHIGS XDWA workstations) requires one
segment that is to be consumed for the duration of an open graPHIGS XDWA
(direct access) workstation.  This segment must be one of the segments (3 -
 12).

The display subsystem uses shared memory to improve performance when
graphics processes are communicating through socket connections. Shared
memory connections, established when the DISPLAY environment variable is
set to its normal default (:0.0), consume one segment each. There
are two connections used by a typical application that uses the graPHIGS
API. One is the connection between the application and the X Server, and
the other is the connection between the graPHIGS API and the X Server.
If the DISPLAY environment variable is modified to specify UNIX domain
sockets (unix:0.0) or TCP/IP sockets (<hostname>:0.0), then no segments
are consumed for shared memory connections.  Therefore, an application or
user can control use of these segments and have more segments for
application use.

For the GXT3000P and GXT2000P in the 4.3.3 environment the default graPHIGS
 API and application usage, the application has 7 segments
(1.75 GB) available.  Exceptions to this include:

   -  If the user or application sets the DISPLAY environment variable to
use UNIX domain sockets or TCP/IP sockets, two more segments
      become available and the application can access up to 2 GB data for
the Large Program Support model.  Note: The AIX Operating
      System has a maximum of 8 segments available for Large Program
Support.

   -  If the application has selected to use an 8 segment Large Program
Model and the application obtains its display connection before
      opening the graPHIGS workstation, then the graPHIGS API uses the last
 available segment for adapter I/O and the DISPLAY connection
      is then UNIX domain sockets.  Note: The application connection to the
 X Server is still a shared memory connection.

If an application uses shmat or mmap, and not the Large Program Support, it
 could access up to 10 segments or 2.5 GB of shared memory  (9 total
segments consisting of segment numbers 3-12 and 14) or 2.25GB of contiguous
 shared memory (segments 3-11 or segments 4-12), and still
use an XDWA workstation. This requires that the application open the XDWA
workstation before all segments in the 3-12 range are consumed.
This also requires that the user sets the DISPLAY environment variable to
specify UNIX domain sockets or TCP/IP sockets for all X Window System
connections.

Note: When Unix domain sockets are specified, there may be reduced
performance for applications using input events which are passed to
the graPHIGS API from the X Server.

Multiple graPHIGS XDWA workstations opened on the same adapter only require
 one segment per process for adapter I/O.