DPL: enable prefetching only for branches with one basket

ktf · ktf · commit f8a68d8a42e6 · 2024-10-04T10:04:30.000+02:00
diff --git a/Framework/Core/src/TableTreeHelpers.cxx b/Framework/Core/src/TableTreeHelpers.cxx
@@ -552,7 +552,11 @@ void TreeToTable::addAllColumns(TTree* tree, std::vector<std::string>&& names)
   tree->SetCacheSize(25000000);
   tree->SetClusterPrefetch(true);
   for (auto& reader : mBranchReaders) {
-    tree->AddBranchToCache(reader->branch());
+    // Unfortunately ROOT 6-32-06 is still buggy. Adding a branch to
+    // the cache only if the number of baskets allows it.
+    if (reader->branch()->GetListOfBaskets()->GetEntriesFast() == 1) {
+      tree->AddBranchToCache(reader->branch());
+    }
   }
   tree->StopCacheLearningPhase();
 }

Original file line number	Diff line number	Diff line change
`@@ -552,7 +552,11 @@ void TreeToTable::addAllColumns(TTree* tree, std::vector<std::string>&& names)`
`552`	`552`	`tree->SetCacheSize(25000000);`
`553`	`553`	`tree->SetClusterPrefetch(true);`
`554`	`554`	`for (auto& reader : mBranchReaders) {`
`555`		`- tree->AddBranchToCache(reader->branch());`
	`555`	`+ // Unfortunately ROOT 6-32-06 is still buggy. Adding a branch to`
	`556`	`+ // the cache only if the number of baskets allows it.`
	`557`	`+ if (reader->branch()->GetListOfBaskets()->GetEntriesFast() == 1) {`
	`558`	`+ tree->AddBranchToCache(reader->branch());`
	`559`	`+ }`
`556`	`560`	`}`
`557`	`561`	`tree->StopCacheLearningPhase();`
`558`	`562`	`}`