#2201: created framework to integrate transfer strategy ivar

Author: ppebay

src/vt/vrt/collection/balance/temperedlb/tempered_enums.h

@@ -92,8 +92,8 @@ enum struct TransferTypeEnum : uint8_t {
   /**
    * \brief Form object clusters and attempt to perform swaps.
    *
-   * Object can be clustered including to arbitrary definition, and swaps
-   * of entire clusters, including the nullset, between ranks are attempted.
+   * Object can be clustered according to arbitrary definition, and swaps
+   * of entire clusters, according the nullset, between ranks are attempted.
    * This is especially useful when shared memory constraints are present,
    * as breaking shared memory clusters results in higher overall memory
    * footprint, in constrast with whole cluster swaps.
@@ -195,36 +195,6 @@ enum struct KnowledgeEnum : uint8_t {
   Log         = 2
 };
 
-/// Enum for the strategy to be used in transfer stage
-enum struct TransferStrategyEnum : uint8_t {
-  /**
-   * \brief Original strategy
-   *
-   * Transfer one object per transfer as in original Grapevine approach.
-   */
-  Original   = 0,
-  /**
-   * \brief Original strategy improved by recursion
-   *
-   * When single object transfer is rejected, attempt to recurse in order to
-   * pull more objects into the transfer and hereby minimize work added by
-   * said transfer.
-   * This is especially useful when communication is taken into account, as
-   * object transfers typically disrupt local vs. global communication edges.
-   */
-  Recursive  = 1,
-  /**
-   * \brief Form object clusters and attempt to perform swaps.
-   *
-   * Object can be clustered according to arbitrary definition, and swaps
-   * of entire clusters, according the nullset, between ranks are attempted.
-   * This is especially useful when shared memory constraints are present,
-   * as breaking shared memory clusters results in higher overall memory
-   * footprint, in constrast with whole cluster swaps.
-   */
-  ClusterSwap = 2,
-};
-
 }}}} /* end namespace vt::vrt::collection::lb */
 
 #endif /*INCLUDED_VT_VRT_COLLECTION_BALANCE_TEMPEREDLB_TEMPERED_ENUMS_H*/

src/vt/vrt/collection/balance/temperedlb/temperedlb.h

@@ -172,7 +172,12 @@ struct TemperedLB : BaseLB {
   LoadType target_max_load_                         = 0.0;
   CriterionEnum criterion_                          = CriterionEnum::ModifiedGrapevine;
   InformTypeEnum inform_type_                       = InformTypeEnum::AsyncInform;
-  /// Type of strategy to be used in transfer stage
+  /**
+   * \brief Type of strategy to be used in transfer stage
+   *
+   * Available strategies include: Original, Recursive, and SwapClusters
+   * and are adapted to different kinds of problems.
+   */
   TransferTypeEnum transfer_type_                   = TransferTypeEnum::Original;
   ObjectOrderEnum obj_ordering_                     = ObjectOrderEnum::FewestMigrations;
   CMFTypeEnum cmf_type_                             = CMFTypeEnum::NormByMax;