The DDF domain only has one target. The parameters of the target are:
- maxBufferSize (
INT) Default = 1024
The capacity of an arc (in particles). This is used for the run-time detection of inconsistencies, as explained above. If any arc exceeds this capacity, an error is flagged and the simulation halts. A negative number is interpreted as infinite capacity (unless useFastScheduler is YES). The value of this parameter does not specify how much memory is allocated for the buffers, since the memory is allocated dynamically.
- schedulePeriod (
FLOAT) Default = 0.0
This defines the amount of time taken by one iteration (defined above) of the DDF schedule. This is used only for interface with timed domains, such as DE. Note that if you want the count given in the debug panel of the run control panel to indicate the number of iterations, you should set this parameter to one.
- runUntilDeadlock (
INT) Default = NO
Unless useFastScheduler is set, this modifies the definition of a single iteration to invoke all stars as many times as possible, until the system halts. It is risky to use this because the system may not halt. But in wormholes it is sometimes useful.
- restructure (
INT) Default = NO
This specifies that the experimental scheduler DDFClustSched should be used. This scheduler attempts to form SDF clusters for more efficient execution. Its use is not advised at this time, however, since it does not work properly with wormholes and is slower than the default scheduler.
- useFastScheduler (
INT) Default = NO
This specifies that the older and faster DDF scheduler (from version 0.5.2) should be used. It is difficult, however, to control the length of a run with this scheduler.
- numOverlapped (
INT) Default = 1
For the fast scheduler only, this gives the number of iteration cycles that can be overlapped for execution. When a DDF system starts up, it normally begins by firing each source star once, as explained above. It then goes into a lazy evaluation mode. Setting this parameter to an integer N larger than one allows the scheduler to begin with N firings of the source stars instead of just one. This can make execution more efficient, because stars downstream from the sources will be able to fire multiple times in each pass through the graph. The default value of this parameter is 1.
- logFile (
STRING) Default =
The default is the empty string. If non-empty, this gives the name of a file to be used for recording scheduler information.
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