Merge branch '0.5.1' into '0.5.1'

0.5.1

See merge request megasearch/milvus!806

Former-commit-id: 2d2be275c77cd249258a309f4a12ca6d67eafa94

core/src/scheduler/job/SearchJob.h

@@ -90,6 +90,11 @@ class SearchJob : public Job {
         return index_files_;
     }
 
+    std::mutex&
+    mutex() {
+        return mutex_;
+    }
+
  private:
     uint64_t topk_ = 0;
     uint64_t nq_ = 0;

core/src/scheduler/task/SearchTask.cpp

@@ -219,8 +219,11 @@ XSearchTask::Execute() {
 
             // step 3: pick up topk result
             auto spec_k = index_engine_->Count() < topk ? index_engine_->Count() : topk;
+            {
+                std::unique_lock<std::mutex> lock(search_job->mutex());
                 XSearchTask::MergeTopkToResultSet(output_ids, output_distance, spec_k, nq, topk, metric_l2,
                                                   search_job->GetResult());
+            }
 
             span = rc.RecordSection(hdr + ", reduce topk");
             //            search_job->AccumReduceCost(span);