refactor: move random number generator into collisions

libs/runcleo/runcleo.hpp

@@ -8,7 +8,7 @@
  * Author: Clara Bayley (CB)
  * Additional Contributors: Tobias Kölling (TK)
  * -----
- * Last Modified: Friday 19th April 2024
+ * Last Modified: Wednesday 8th May 2024
  * Modified By: CB
  * -----
  * License: BSD 3-Clause "New" or "Revised" License
@@ -27,7 +27,6 @@
 #include <Kokkos_Random.hpp>
 #include <concepts>
 #include <iostream>
-#include <random>
 #include <stdexcept>
 #include <string>
 
@@ -116,11 +115,10 @@ class RunCLEO {
    * @param t_end End time for timestepping.
    * @param gbxs DualView of gridboxes.
    * @param totsupers View of all superdroplets (both in and out of bounds of domain).
-   * @param genpool Random number generator pool.
    * @return 0 on success.
    */
-  int timestep_cleo(const unsigned int t_end, const dualview_gbx gbxs, const viewd_supers totsupers,
-                    GenRandomPool genpool) const {
+  int timestep_cleo(const unsigned int t_end, const dualview_gbx gbxs,
+                    const viewd_supers totsupers) const {
     std::cout << "\n--- timestepping ---\n";
 
     unsigned int t_mdl(0);
@@ -132,7 +130,7 @@ class RunCLEO {
       coupldyn_step(t_mdl, t_next);
 
       /* advance SDM (optionally concurrent to dynamics solver) */
-      sdm_step(t_mdl, t_next, gbxs, totsupers, genpool);
+      sdm_step(t_mdl, t_next, gbxs, totsupers);
 
       /* proceed to next step (in general involves coupling) */
       t_mdl = proceed_to_next_step(t_next, gbxs);
@@ -217,12 +215,11 @@ class RunCLEO {
    * @param t_next Next timestep of the coupled model.
    * @param gbxs DualView of gridboxes.
    * @param totsupers View of all superdrops (both in and out of bounds of domain).
-   * @param genpool Random number generator pool.
    */
   void sdm_step(const unsigned int t_mdl, unsigned int t_next, dualview_gbx gbxs,
-                const viewd_supers totsupers, GenRandomPool genpool) const {
+                const viewd_supers totsupers) const {
     gbxs.sync_device();  // get device up to date with host
-    sdm.run_step(t_mdl, t_next, gbxs.view_device(), totsupers, genpool);
+    sdm.run_step(t_mdl, t_next, gbxs.view_device(), totsupers);
     gbxs.modify_device();  // mark device view of gbxs as modified
   }
 
@@ -297,13 +294,12 @@ class RunCLEO {
     // create runtime objects
     viewd_supers totsupers(create_supers(initconds.initsupers));
     dualview_gbx gbxs(create_gbxs(sdm.gbxmaps, initconds.initgbxs, totsupers));
-    GenRandomPool genpool(std::random_device {}());
 
     // prepare CLEO for timestepping
     prepare_to_timestep(gbxs);
 
     // do timestepping from t=0 to t=t_end
-    timestep_cleo(t_end, gbxs, totsupers, genpool);
+    timestep_cleo(t_end, gbxs, totsupers);
 
     return 0;
   }

libs/runcleo/sdmmethods.hpp

@@ -8,7 +8,7 @@
  * Author: Clara Bayley (CB)
  * Additional Contributors: Tobias Kölling (TK)
  * -----
- * Last Modified: Friday 19th April 2024
+ * Last Modified: Wednesday 8th May 2024
  * Modified By: CB
  * -----
  * License: BSD 3-Clause "New" or "Revised" License
@@ -126,10 +126,9 @@ class SDMMethods {
      * @param t_sdm Current timestep for SDM.
      * @param t_next Next timestep for SDM.
      * @param d_gbxs View of gridboxes on device.
-     * @param genpool Random number generator pool.
      */
-    void operator()(const unsigned int t_sdm, const unsigned int t_next, const viewd_gbx d_gbxs,
-                    GenRandomPool genpool) const {
+    void operator()(const unsigned int t_sdm, const unsigned int t_next,
+                    const viewd_gbx d_gbxs) const {
       // TODO(all) use scratch space for parallel region?
       const size_t ngbxs(d_gbxs.extent(0));
       Kokkos::parallel_for(
@@ -139,7 +138,7 @@ class SDMMethods {
 
             auto supers(d_gbxs(ii).supersingbx());
             for (unsigned int subt = t_sdm; subt < t_next; subt = microphys.next_step(subt)) {
-              supers = microphys.run_step(team_member, subt, supers, d_gbxs(ii).state, genpool);
+              supers = microphys.run_step(team_member, subt, supers, d_gbxs(ii).state);
             }
           });
     }
@@ -214,16 +213,15 @@ class SDMMethods {
    * @param t_mdl_next Next timestep of the coupled model.
    * @param d_gbxs View of gridboxes on device.
    * @param totsupers View of all superdrops (both in and out of bounds of domain).
-   * @param genpool Random number generator pool.
    */
   void run_step(const unsigned int t_mdl, const unsigned int t_mdl_next, viewd_gbx d_gbxs,
-                const viewd_supers totsupers, GenRandomPool genpool) const {
+                const viewd_supers totsupers) const {
     unsigned int t_sdm(t_mdl);
     while (t_sdm < t_mdl_next) {
       const auto t_sdm_next = next_sdmstep(t_sdm, t_mdl_next);
 
-      superdrops_movement(t_sdm, d_gbxs, totsupers);         // on host and device
-      sdm_microphysics(t_sdm, t_sdm_next, d_gbxs, genpool);  // on device
+      superdrops_movement(t_sdm, d_gbxs, totsupers);  // on host and device
+      sdm_microphysics(t_sdm, t_sdm_next, d_gbxs);    // on device
 
       t_sdm = t_sdm_next;
     }

libs/superdrops/collisions/collisions.hpp

@@ -9,7 +9,7 @@
  * Author: Clara Bayley (CB)
  * Additional Contributors:
  * -----
- * Last Modified: Sunday 21st April 2024
+ * Last Modified: Wednesday 8th May 2024
  * Modified By: CB
  * -----
  * License: BSD 3-Clause "New" or "Revised" License
@@ -25,6 +25,7 @@
 #include <Kokkos_Core.hpp>
 #include <Kokkos_Random.hpp>
 #include <concepts>
+#include <random>
 
 #include "../../cleoconstants.hpp"
 #include "../kokkosaliases_sd.hpp"
@@ -79,6 +80,7 @@ struct DoCollisions {
   const double DELT; /**< time interval [s] over which probability of collision is calculated. */
   const Probability probability; /**< Probability object for calculating collision probabilities. */
   const EnactCollision enact_collision; /**< Enactment object for enacting collision events. */
+  const GenRandomPool genpool;          /**< Kokkos thread-safe random number generator pool.*/
 
   /**
    * @brief Scaled probability of collision for a pair of super-droplets.
@@ -132,13 +134,12 @@ struct DoCollisions {
    *
    * @param dropA The first superdroplet.
    * @param dropB The second superdroplet.
-   * @param genpool The random number generator pool.
    * @param scale_p The scaling factor.
    * @param VOLUME The volume.
    * @return True if the collision event results in null superdrops with xi=0), otherwise false.
    */
   KOKKOS_INLINE_FUNCTION bool collide_superdroplet_pair(Superdrop &dropA, Superdrop &dropB,
-                                                        GenRandomPool genpool, const double scale_p,
+                                                        const double scale_p,
                                                         const double VOLUME) const {
     /* 1. assign references to each superdrop in pair
     that will collide such that (drop1.xi) >= (drop2.xi) */
@@ -176,12 +177,10 @@ struct DoCollisions {
    * @param team_member The Kokkos team member.
    * @param supers The randomly shuffled view of super-droplets.
    * @param volume The volume in which to calculate the probability of collisions.
-   * @param genpool The random number generator pool.
    * @return The number of null (xi=0) superdrops.
    */
   KOKKOS_INLINE_FUNCTION size_t collide_supers(const TeamMember &team_member,
-                                               subviewd_supers supers, const double volume,
-                                               GenRandomPool genpool) const {
+                                               subviewd_supers supers, const double volume) const {
     const auto nsupers = static_cast<size_t>(supers.extent(0));
     const auto npairs = size_t{nsupers / 2};  // no. pairs of superdrops (=floor() for nsupers > 0)
     const auto scale_p = double{nsupers * (nsupers - 1.0) / (2.0 * npairs)};
@@ -193,7 +192,7 @@ struct DoCollisions {
         [&, this](const size_t jj, size_t &nnull) {
           const auto kk = size_t{jj * 2};
           const auto isnull =
-              collide_superdroplet_pair(supers(kk), supers(kk + 1), genpool, scale_p, VOLUME);
+              collide_superdroplet_pair(supers(kk), supers(kk + 1), scale_p, VOLUME);
           nnull += static_cast<size_t>(isnull);
         },
         totnnull);
@@ -212,19 +211,17 @@ struct DoCollisions {
    * @param team_member The Kokkos team member.
    * @param supers The view of super-droplets.
    * @param volume The volume in which to calculate the probability of collisions.
-   * @param genpool The random number generator pool.
    * @return The updated superdroplets.
    */
   KOKKOS_INLINE_FUNCTION subviewd_supers do_collisions(const TeamMember &team_member,
-                                                       subviewd_supers supers, const double volume,
-                                                       GenRandomPool genpool) const {
+                                                       subviewd_supers supers,
+                                                       const double volume) const {
     /* Randomly shuffle order of superdroplet objects
     in supers in order to generate random pairs */
     supers = one_shuffle_supers(team_member, supers, genpool);
 
     /* collide all randomly generated pairs of SDs */
-    size_t nnull(
-        collide_supers(team_member, supers, volume, genpool));  // number of null superdrops
+    size_t nnull(collide_supers(team_member, supers, volume));  // number of null superdrops
 
     return is_null_supers(supers, nnull);
   }
@@ -242,7 +239,7 @@ struct DoCollisions {
    * @param x The enactment object for enacting collision events.
    */
   DoCollisions(const double DELT, Probability p, EnactCollision x)
-      : DELT(DELT), probability(p), enact_collision(x) {}
+      : DELT(DELT), probability(p), enact_collision(x), genpool(std::random_device {}()) {}
 
   /**
    * @brief Operator used as an "adaptor" for using collisions as the MicrophysicsFunction type for
@@ -258,14 +255,12 @@ struct DoCollisions {
    * @param subt The sub-time step.
    * @param supers The superdroplets.
    * @param state The state.
-   * @param genpool The random number generator pool.
    * @return The updated superdroplets.
    */
   KOKKOS_INLINE_FUNCTION subviewd_supers operator()(const TeamMember &team_member,
                                                     const unsigned int subt, subviewd_supers supers,
-                                                    const State &state,
-                                                    GenRandomPool genpool) const {
-    return do_collisions(team_member, supers, state.get_volume(), genpool);
+                                                    const State &state) const {
+    return do_collisions(team_member, supers, state.get_volume());
   }
 };
 

libs/superdrops/condensation.hpp

@@ -8,7 +8,7 @@
  * Author: Clara Bayley (CB)
  * Additional Contributors: Shin-ichiro Shima (SiS)
  * -----
- * Last Modified: Wednesday 17th April 2024
+ * Last Modified: Wednesday 8th May 2024
  * Modified By: CB
  * -----
  * License: BSD 3-Clause "New" or "Revised" License
@@ -165,12 +165,11 @@ struct DoCondensation {
    * @param subt The microphysics time step.
    * @param supers The view of super-droplets.
    * @param state The State.
-   * @param genpool The Kokkos thread-safe random number generator pool.
    * @return The updated view super-droplets.
    */
   KOKKOS_INLINE_FUNCTION subviewd_supers operator()(const TeamMember &team_member,
                                                     const unsigned int subt, subviewd_supers supers,
-                                                    State &state, GenRandomPool genpool) const {
+                                                    State &state) const {
     do_condensation(team_member, supers, state);
     return supers;
   }

libs/superdrops/microphysicalprocess.hpp

@@ -8,7 +8,7 @@
  * Author: Clara Bayley (CB)
  * Additional Contributors: Tobias Kölling (TK)
  * -----
- * Last Modified: Monday 12th February 2024
+ * Last Modified: Wednesday 8th May 2024
  * Modified By: CB
  * -----
  * License: BSD 3-Clause "New" or "Revised" License
@@ -23,10 +23,9 @@
 #ifndef LIBS_SUPERDROPS_MICROPHYSICALPROCESS_HPP_
 #define LIBS_SUPERDROPS_MICROPHYSICALPROCESS_HPP_
 
-#include <concepts>
-
 #include <Kokkos_Core.hpp>
 #include <Kokkos_Random.hpp>
+#include <concepts>
 
 #include "../cleoconstants.hpp"
 #include "./kokkosaliases_sd.hpp"
@@ -44,10 +43,10 @@
  */
 template <typename P>
 concept MicrophysicalProcess = requires(P p, const TeamMember &tm, const unsigned int t,
-                                        subviewd_supers supers, State &state, GenRandomPool gp) {
+                                        subviewd_supers supers, State &state) {
   { p.next_step(t) } -> std::convertible_to<unsigned int>;
   { p.on_step(t) } -> std::same_as<bool>;
-  { p.run_step(tm, t, supers, state, gp) } -> std::convertible_to<subviewd_supers>;
+  { p.run_step(tm, t, supers, state) } -> std::convertible_to<subviewd_supers>;
 };
 
 /**
@@ -64,8 +63,8 @@ concept MicrophysicalProcess = requires(P p, const TeamMember &tm, const unsigne
 template <MicrophysicalProcess Microphys1, MicrophysicalProcess Microphys2>
 struct CombinedMicrophysicalProcess {
  private:
-  Microphys1 a;   /**< The first instance of type of MicrophysicalProcess. */
-  Microphys2 b;   /**< The second instance of type of MicrophysicalProcess. */
+  Microphys1 a; /**< The first instance of type of MicrophysicalProcess. */
+  Microphys2 b; /**< The second instance of type of MicrophysicalProcess. */
 
  public:
   /**
@@ -106,14 +105,13 @@ struct CombinedMicrophysicalProcess {
    * @param subt The current time step.
    * @param supers The view of super-droplets.
    * @param state The state of the system / volume.
-   * @param genpool The Kokkos thread-safe random number generator pool.
    * @return The updated view of super-droplets after the process.
    */
   KOKKOS_INLINE_FUNCTION subviewd_supers run_step(const TeamMember &team_member,
                                                   const unsigned int subt, subviewd_supers supers,
-                                                  State &state, GenRandomPool genpool) const {
-    supers = a.run_step(team_member, subt, supers, state, genpool);
-    supers = b.run_step(team_member, subt, supers, state, genpool);
+                                                  State &state) const {
+    supers = a.run_step(team_member, subt, supers, state);
+    supers = b.run_step(team_member, subt, supers, state);
     return supers;
   }
 };
@@ -167,12 +165,11 @@ struct NullMicrophysicalProcess {
    * @param subt The current time step.
    * @param supers The view of super-droplets.
    * @param state The state of the system.
-   * @param genpool The random number generator pool.
    * @return The unchanged view of super-droplets.
    */
   KOKKOS_INLINE_FUNCTION subviewd_supers run_step(const TeamMember &team_member,
                                                   const unsigned int subt, subviewd_supers supers,
-                                                  State &state, GenRandomPool genpool) const {
+                                                  State &state) const {
     return supers;
   }
 };
@@ -187,8 +184,8 @@ struct NullMicrophysicalProcess {
  */
 template <typename F>
 concept MicrophysicsFunc = requires(F f, const TeamMember &tm, const unsigned int subt,
-                                    subviewd_supers supers, State &state, GenRandomPool gp) {
-  { f(tm, subt, supers, state, gp) } -> std::convertible_to<subviewd_supers>;
+                                    subviewd_supers supers, State &state) {
+  { f(tm, subt, supers, state) } -> std::convertible_to<subviewd_supers>;
 };
 
 /**
@@ -203,8 +200,8 @@ concept MicrophysicsFunc = requires(F f, const TeamMember &tm, const unsigned in
 template <MicrophysicsFunc F>
 struct ConstTstepMicrophysics {
  private:
-  unsigned int interval;   /**< The constant time step between calls to microphysics. */
-  F do_microphysics;       /**< Function-like microphysics is type of MicrophysicsFunc*/
+  unsigned int interval; /**< The constant time step between calls to microphysics. */
+  F do_microphysics;     /**< Function-like microphysics is type of MicrophysicsFunc*/
 
  public:
   /**
@@ -244,14 +241,13 @@ struct ConstTstepMicrophysics {
    * @param subt The current time step.
    * @param supers The view of super-droplets.
    * @param state The state of the system / volume.
-   * @param genpool The Kokkos thread-safe random number generator pool.
    * @return The updated view of super-droplets after the process.
    */
   KOKKOS_INLINE_FUNCTION subviewd_supers run_step(const TeamMember &team_member,
                                                   const unsigned int subt, subviewd_supers supers,
-                                                  State &state, GenRandomPool genpool) const {
+                                                  State &state) const {
     if (on_step(subt)) {
-      supers = do_microphysics(team_member, subt, supers, state, genpool);
+      supers = do_microphysics(team_member, subt, supers, state);
     }
 
     return supers;

libs/superdrops/urbg.hpp

@@ -8,7 +8,7 @@
  * Author: Clara Bayley (CB)
  * Additional Contributors:
  * -----
- * Last Modified: Tuesday 9th April 2024
+ * Last Modified: Wednesday 8th May 2024
  * Modified By: CB
  * -----
  * License: BSD 3-Clause "New" or "Revised" License
@@ -132,7 +132,7 @@ KOKKOS_INLINE_FUNCTION viewd_supers shuffle_supers(const viewd_supers supers,
  */
 KOKKOS_INLINE_FUNCTION viewd_supers one_shuffle_supers(const TeamMember& team_member,
                                                        const viewd_supers supers,
-                                                       GenRandomPool genpool) {
+                                                       const GenRandomPool genpool) {
   Kokkos::single(Kokkos::PerTeam(team_member), [&]() {
     URBG<ExecSpace> urbg{genpool.get_state()};
     shuffle_supers(supers, urbg);