Measure Reference Manual

try allocating more data pages with the TAL compiler ?DATAPAGES command or the RUN command
MEM parameter.
Maintaining Compatibility With New Structures in MEASDDLS and MEASCHMA
In some instances, a recompile is required for C and C++ applications. For example, G08 Measure
redefines the MODULE and SUBDEVICE fields of the SERVERNET entity descriptor as the ServerNet
Cluster NODE number and CPU number of the remote system's processor. For C or C++ applications
that use the Measure callable procedures to configure ServerNet measurements that use the new
structures provided by MEASDDLS and MEASCHMA, a recompile is required. These redefined
fields must be accessed as members of a union.
Using Timer Cells
H-series Measure introduces a timer-cell facility, which improves the accuracy of timer calculations
for events that complete within the context of a dispatch or a simple message exchange between
two processes in the same processor. This mechanism lets you keep fine-granularity timers without
incurring the cost of loose processor synchronization on all timer updates. Timer cell values are
synchronized only when copied at intervals or reported to the requesting application.
Counter types associated with the timer cell mechanism are:
• TCELLBUSY. This counter type is equivalent to a conventional BUSY counter but is implemented
with timer cells.
• TCELLQUEUE. This counter type is equivalent to a conventional QUEUE counter but is
implemented with timer cells.
• TCELLQBUSY. This counter type is equivalent to a conventional QBUSY counter but is
implemented with timer cells.
For USERDEF counters, you can take advantage of the timer-cell mechanism by defining counters
of the new types. For example, if an application ran on an G-series RVU and you now plan to run
it on an H-series or J-series RVU, consider redefining Busy, Queue, and Queue Busy timers if the
events they measure occur at fine intervals. Events that involve interprocessor communication or
I/O need not be redefined, because in such cases, loose processor synchronization has little or
no impact.
Redefining a USERDEF counter to use timer cells does not necessitate application changes. Although
new callable procedures support the timer-cell mechanism, Measure calls those procedures implicitly
to maintain timer-cell counters that you define for USERDEF entities. The only change required is
in the configuration of the USERDEF entity, where you specify that a counter is of one of the new
types.
Use the timer-cell calls explicitly only if your application maintains counters outside of Measure.
For more information, refer to the descriptions of MEAS_ALLOCATE_TIMERCELLS_,
MEAS_DEALLOCATE_TIMERCELLS_ , MEAS_BUMP_TIMERCELL_, and
MEAS_RETRIEVE_TIMERCELLS_.
Measure Procedures Overview 379