Configuration File

To start, here is the configuration file:

<?xml version="1.0" ?>
<arcane-config code-name="Quicksilver">
  <time-loops>
    <time-loop name="QAMALoop">
      <title>QS</title>
      <description>Default timeloop for code Quicksilver Arcane MiniApp
      </description>
 
      <singleton-services>
        <service name="SimpleCsvOutput" need="required"/>
        <service name="SimpleCsvComparator" need="required"/>
        <service name="RNG" need="required"/>
      </singleton-services>
 
      <modules>
        <module name="QS" need="required"/>
        <module name="SamplingMC" need="required"/>
        <module name="TrackingMC" need="required"/>
      </modules>
 
      <entry-points where="init">
        <entry-point name="QS.InitModule"/>
        <entry-point name="SamplingMC.InitModule"/>
        <entry-point name="TrackingMC.InitModule"/>
        <entry-point name="QS.StartLoadBalancing"/>
      </entry-points>
 
      <entry-points where="compute-loop">
        <entry-point name="SamplingMC.CycleSampling"/>
        <entry-point name="TrackingMC.CycleTracking"/>
        <entry-point name="QS.CycleFinalize"/>
        <entry-point name="SamplingMC.CycleFinalize"/>
        <entry-point name="TrackingMC.CycleFinalize"/>
        <entry-point name="QS.LoopLoadBalancing"/>
      </entry-points>
 
      <entry-points where="on-mesh-changed">
        <entry-point name="QS.AfterLoadBalancing"/>
      </entry-points>
 
      <entry-points where="exit">
        <entry-point name="SamplingMC.EndModule"/>
        <entry-point name="TrackingMC.EndModule"/>
        <entry-point name="QS.CompareWithReference"/>
        <entry-point name="QS.EndModule"/>
      </entry-points>
 
    </time-loop>
  </time-loops>
</arcane-config>

With this file, we can already see what QAMA looks like. We find our three modules QS, SamplingMC, and TrackingMC in the<modules> section. We also find the three types of entry points that we saw in the HelloWorld example: init, compute-loop, and exit (here: SayHello.axl).

Note

In HelloWorld, there was only one entry point per entry point type, so there was no need to worry about the order. Here, we have several. It is therefore important to note that the order of entry points is important and is taken into account. Conversely, the order of entry point types is not important.

<!-- 1) -->
<entry-points where="compute-loop">
  <entry-point name="SamplingMC.CycleSampling" />
  <entry-point name="TrackingMC.CycleTracking" />
</entry-points>
 
<entry-points where="init">
  <entry-point name="QS.InitModule" />
  <entry-point name="SamplingMC.InitModule" />
</entry-points>

gives the same result as:

<!-- 2) -->
<entry-points where="init">
  <entry-point name="QS.InitModule" />
  <entry-point name="SamplingMC.InitModule" />
</entry-points>
 
<entry-points where="compute-loop">
  <entry-point name="SamplingMC.CycleSampling" />
  <entry-point name="TrackingMC.CycleTracking" />
</entry-points>

but is different from:

<!-- 3) -->
<entry-points where="init">
  <entry-point name="SamplingMC.InitModule"/> <!-- here -->
  <entry-point name="QS.InitModule"/>         <!-- here -->
</entry-points>
 
<entry-points where="compute-loop">
  <entry-point name="SamplingMC.CycleSampling" />
  <entry-point name="TrackingMC.CycleTracking" />
</entry-points>

---

In the new features, we first have the <singleton-services> section. We find the service seen in the previous section: RNG. We also have two other services: Arcane::SimpleCsvOutput and Arcane::SimpleCsvComparator. These services are services included in the Arcane framework and can therefore be used by any application.

Their interfaces are available in this documentation: Arcane::ISimpleTableOutput, Arcane::ISimpleTableComparator, and Arcane::IRandomNumberGenerator.

Like the RNG service, it is possible to create an implementation specific to our application using the interface of these services.

---

There are two ways to use a service:

• as a normal service, which must be declared in the .axl of a module. In this case, there will be one object per module that declares it, and it will not be shared.
• as a singleton, which must be declared in the project's .config. In this case, there will only be one object per project. Modules can retrieve a pointer to this unique object.

In QAMA, I chose the singleton method. For the SimpleCsvOutput service, it is necessary to share the object to generate a single CSV table. For the RNG service, it doesn't matter.

Warning

In the case of a singleton, it is impossible to retrieve data from the dataset autonomously. However, it is possible to pass the data through one of the present modules. In the case of Quicksilver, it is the QSModule that is responsible for doing this. It is possible to determine, for a service, whether it is considered a singleton with this line:

option() == null;

If there are options, then we are in a classic service; otherwise, we are in a singleton.

---

We also have a new type of entry point: on-mesh-changed. This type of entry point is triggered when the mesh changes, for example, during a redistribution. This entry point executes after compute-loop type entry points.

Warning

In practice, if you retrieve m_global_iteration() in a compute-loop type entry point, you will get iteration i (example: QS.LoopLoadBalancing), then in the next on-mesh-changed type entry point, you will get iteration i+1 (example: QS.AfterLoadBalancing).

---

General Structure RNG Service