GDSX (Extended General Device Support) Manual

Operations and Support
Extended General Device Support (GDSX) Manual—529931-001
3-12
Space Usages and Limitations
= SET SERVER PARAM PROCNOWAIT 1 Run in nowait mode
= SET SERVER PARAM SERVER 1 Run as a server
= SET SERVER PARAM NONSTOP 1 Run in NonStop mode
= ADD SERVER GDSX-SERVER Name of server class
= START SERVER GDSX-SERVER Start the GDSX server
Space Usages and Limitations
Because USCODE is bound with TSCODE to become a GDSX runnable unit, there are
limitations in code space and data space in user code. However, because multiple
code spaces are available, code space is not likely to be a problem.
Regarding the data space, GDSX uses a user data segment with a size of 64 pages.
TSCODE uses two extended segments—one for various control and data structures
and one for trace data. The segment allocated by default for the control and data
structures is segment ID 1024. Segment ID 1025 is always allocated for the trace
data. Segment IDs from 1024 up are reserved for TSCODE.
Although it is generally not advisable, USCODE can use its own extended segment
through calls to ALLOCATESEGMENT and USESEGMENT. The segment IDs
available to USCODE range from 0 to 1023.
User Data Segment
The user data segment of the GDSX process is specified at bind time to have a size of
64K words. The size of various areas within the segment is determined by the
configuration parameters. (See GDSX Configuration Parameters on page 2-46 and
3-13.)
Extended Segment
GDSX allocates an extended segment (with default segment ID 1024) and a size
determined by the configuration parameters. If the space is not available, GDSX will
not run, and an internal error message is created—abend error 30.
Extended Segments for Trace Files
When the trace facility is turned on in the primary GDSX process, TSCODE allocates
an extended segment with segment ID 1025, a default size of 64 pages, and the
default file name TRACEP under the default subvolume. The SCF TRACE command
may be used to specify a different file name, and the USER^OPEN^TRACE^FILE
procedure may be used to specify a different file size. (For further information
regarding the trace facility, see Tracing GDSX on page 2-80.)
When the trace facility is turned on in the backup process, TSCODE allocates an
extended segment with segment ID 1025, a default size of 64 pages, and the file name
TRACEB under the default subvolume.