Subsystem Control Point (SCP) Management Programming Manual

Tr ac ing
Subsystem Control Point (SCP) Management Programming Manual—520619-001
B-9
The Trace Information Structure
ZCNT
specifies the maximum number of trace records to be collected. Valid values are:
ZXDS-PAGES
specifies the number of pages allocated for trace records in the trace data extended
data segment. (The actual size of the segment is greater to account for segment
management information.) Valid values are:
ZCOLL
specifies whether the trace is to the extended data segment or to disk. Valid values
are:
ZFNAME
is the name of the disk file to which trace information is written. If ZFNAME is
empty and ZSTOP is not TRUE, the current trace is modified. If ZFNAME contains a
file name and ZSTOP is not TRUE, a new trace is initiated. (If ZSTOP is TRUE, the
trace stops regardless of the value of ZFNAME.)
The default value for ZFNAME is blank.
ZWRAP
specifies whether to wrap data in the trace collector file or the extended segment.
Possible values are:
0 When modifying a trace, the current maximum is retained.
When starting a trace, this value is equivalent to -1.
-1 Records are collected until the trace is stopped or until end-of-
file is encountered on the collector file (if ZWRAP is set to
FALSE).
1 through (2**32)-1 Tracing stops after the specified number of records is
captured.
0 64 pages are allocated.
4 through 1024 The specified number of pages is allocated.
ZSPI-VAL-TRUE or blank The collector actively writes blocks of trace records
from the extended segment to the trace-data disk file.
ZSPI-VAL-FALSE The only records that the collector writes to the disk file
are those in the extended segment when the trace stops.
ZSPI-VAL-TRUE Wrap the trace records (overwrite the beginning of the
disk file or memory segment when it is full). If ZCOLL
is TRUE, this applies to the disk file only; the extended
segment is always allowed to wrap. If ZCOLL is
FALSE, this applies to the extended segment only.
ZSPI-VAL-FALSE or blank Do not wrap trace records.