Setting up a vector of HighsSearch instances, each corresponding to a…

… different HigshLpRelaxation
ERGO-Code · Jan 22, 2025 · e961267 · e961267
1 parent a27aea7
commit e961267
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Showing 2 changed files with 9 additions and 5 deletions.
diff --git a/src/lp_data/HighsOptions.h b/src/lp_data/HighsOptions.h
@@ -1083,7 +1083,7 @@ class HighsOptions : public HighsOptionsStruct {
 
     record_int = new OptionRecordInt(
         "mip_search_concurrency", "Concurrency to use in MIP search", advanced,
-        &mip_search_concurrency, 1, 1, kMipSearchConcurrencyLimit);
+        &mip_search_concurrency, 1, 2, kMipSearchConcurrencyLimit);
     records.push_back(record_int);
 
     record_int = new OptionRecordInt(

diff --git a/src/mip/HighsMipSolver.cpp b/src/mip/HighsMipSolver.cpp
@@ -220,15 +220,19 @@ void HighsMipSolver::run() {
   sepa.setLpRelaxation(&mipdata_->lp);
 
   // Set up a vector of HighsSearch instances, with a
-  // HighsLpRelaxation for each concurrent search
+  // HighsLpRelaxation for each concurrent search beyond the master
+  // search
   std::vector<HighsSearch> multiple_search;
   std::vector<HighsLpRelaxation> multiple_lp;
   for (HighsInt iSearch = 0; iSearch < options_mip_->mip_search_concurrency;
        iSearch++) {
     multiple_search.push_back(HighsSearch{*this, mipdata_->pseudocost});
-    //    multiple_lp.push_back(HighsLpRelaxation{mipdata_->lp});
-    //    multiple_search[iSearch].setLpRelaxation(&multiple_lp[iSearch]);
-    multiple_search[iSearch].setLpRelaxation(&mipdata_->lp);
+    if (iSearch == 0) {
+      multiple_search[iSearch].setLpRelaxation(&mipdata_->lp);
+    } else {
+      multiple_lp.push_back(HighsLpRelaxation{mipdata_->lp});
+      multiple_search[iSearch].setLpRelaxation(&multiple_lp[iSearch-1]);
+    }
   }
   HighsSearch& search = multiple_search[0];