Appendix D. Gddm Release 4 Performance Improvements - IBM 3270 G Manual

Appendix D. GDDM Release 4 Performance
Improvements
GDDM Release 4 continues to consolidate the performance improvements
introduced in Release 3. This appendix describes the performance
improvements that can be expected.
Note: Any claim made in this appendix is subject to validation and
confirmation in the General Availability announcement for GDDM Release
4.
The main changes result from support for the 5279 and 5379 work stations.
These work stations offer:
• Vector-to-raster conversion in the work station
• Picture manipulation in the work station.
Graphics interactions for the 5279 and 5379 have the following differences
compared with similar interactions on the 3279:
• Reduced host path length
The graphics portion of a typical 3279 application program may be
reduced by between 60% and 80%.
Because there are significant nongraphics operations, the total CPU
requirement of a representative GDDM Interactive Chart Utility session
(80% of the interactions being alphanumeric panel display) is expected
to reduce by 20-40% by changing to a 5279 or 5379.
• Data Streams
Typical business graphs displayed on a 3279 have data streams in the
range 10-30K bytes; this can be compressed to 5-15K bytes for remote
operation. A typical ICU business chart using graphics text from the
default symbol sets produces a data stream of less than 5K bytes when
displayed on a 5279 or 5379.
For the representative ICU session defined above, total data stream is
expected to drop by 5-30% for the 5279 or 5379 compared with a remote
(compressed) 3279. The data streams associated with the alphanumeric
panel displays are unaffected by the type of work station on which the
application program is being run.
Appendix D. GDDM Release
4
Performance Improvements
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