THREADNUM= enables you
to specify the maximum number of
I/O threads that the SPD Engine spawns
for processing an SPD Engine data set. The THREADNUM= value applies
to any of the following SPD Engine
I/O processing:
-
WHERE expression processing
-
-
I/O requested by thread-enabled
applications
Adjusting THREADNUM=
enables the system administrator to adjust the level of CPU resources
the SPD Engine can use for any process. For example, in a 64-bit processor
system, setting THREADNUM=4 limits the process to, at most, four CPUs,
thereby enabling greater throughput for other users or applications.
When THREADNUM= is greater
than 1, parallel processing is likely to occur. Therefore, physical
order might not be retained in the output. Setting THREADNUM=1 means
that no parallel processing occurs
You can also use this
option to explore scalability for WHERE expression evaluations.
SPDEMAXTHREADS=, a configurable
system option, imposes an upper limit on the consumption of system
resources and therefore constrains the THREADNUM= value.