From 005d178a0ebae8e35d27a33afa1896c724dc383a Mon Sep 17 00:00:00 2001
From: yah01 <yang.cen@zilliz.com>
Date: Mon, 20 Mar 2023 10:19:56 +0800
Subject: [PATCH] Optimize performance of insert & query & search (#22829)

- Reduce 1x copy of inserting int8/int16 into growing segment
- Reduce 1x copy of retrieving primary keys
- Reduce 1x copy of inserting/loading/deleting/filtering primary keys
- Reduce 1x copy of reducing string results

Signed-off-by: yah01 <yang.cen@zilliz.com>
---
 internal/core/src/segcore/ConcurrentVector.cpp | 8 ++++----
 internal/core/src/segcore/SegmentInterface.cpp | 7 ++++---
 internal/core/src/segcore/Utils.cpp            | 6 +++---
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/internal/core/src/segcore/ConcurrentVector.cpp b/internal/core/src/segcore/ConcurrentVector.cpp
index 32cee42b83..88ef77be05 100644
--- a/internal/core/src/segcore/ConcurrentVector.cpp
+++ b/internal/core/src/segcore/ConcurrentVector.cpp
@@ -39,13 +39,13 @@ VectorBase::set_data_raw(ssize_t element_offset,
                                 element_count);
         }
         case DataType::INT8: {
-            auto src_data = data->scalars().int_data().data();
+            auto& src_data = data->scalars().int_data().data();
             std::vector<int8_t> data_raw(src_data.size());
             std::copy_n(src_data.data(), src_data.size(), data_raw.data());
             return set_data_raw(element_offset, data_raw.data(), element_count);
         }
         case DataType::INT16: {
-            auto src_data = data->scalars().int_data().data();
+            auto& src_data = data->scalars().int_data().data();
             std::vector<int16_t> data_raw(src_data.size());
             std::copy_n(src_data.data(), src_data.size(), data_raw.data());
             return set_data_raw(element_offset, data_raw.data(), element_count);
@@ -104,13 +104,13 @@ VectorBase::fill_chunk_data(ssize_t element_count,
                                    element_count);
         }
         case DataType::INT8: {
-            auto src_data = data->scalars().int_data().data();
+            auto& src_data = data->scalars().int_data().data();
             std::vector<int8_t> data_raw(src_data.size());
             std::copy_n(src_data.data(), src_data.size(), data_raw.data());
             return fill_chunk_data(data_raw.data(), element_count);
         }
         case DataType::INT16: {
-            auto src_data = data->scalars().int_data().data();
+            auto& src_data = data->scalars().int_data().data();
             std::vector<int16_t> data_raw(src_data.size());
             std::copy_n(src_data.data(), src_data.size(), data_raw.data());
             return fill_chunk_data(data_raw.data(), element_count);
diff --git a/internal/core/src/segcore/SegmentInterface.cpp b/internal/core/src/segcore/SegmentInterface.cpp
index 6cf7df460c..ba99745609 100644
--- a/internal/core/src/segcore/SegmentInterface.cpp
+++ b/internal/core/src/segcore/SegmentInterface.cpp
@@ -133,16 +133,17 @@ SegmentInternalInterface::Retrieve(const query::RetrievePlan* plan,
             switch (field_meta.get_data_type()) {
                 case DataType::INT64: {
                     auto int_ids = ids->mutable_int_id();
-                    auto src_data = col_data->scalars().long_data();
+                    auto& src_data = col_data->scalars().long_data();
                     int_ids->mutable_data()->Add(src_data.data().begin(),
                                                  src_data.data().end());
                     break;
                 }
                 case DataType::VARCHAR: {
                     auto str_ids = ids->mutable_str_id();
-                    auto src_data = col_data->scalars().string_data();
-                    for (auto i = 0; i < src_data.data_size(); ++i)
+                    auto& src_data = col_data->scalars().string_data();
+                    for (auto i = 0; i < src_data.data_size(); ++i) {
                         *(str_ids->mutable_data()->Add()) = src_data.data(i);
+                    }
                     break;
                 }
                 default: {
diff --git a/internal/core/src/segcore/Utils.cpp b/internal/core/src/segcore/Utils.cpp
index d3081bbce1..89cfcc57e3 100644
--- a/internal/core/src/segcore/Utils.cpp
+++ b/internal/core/src/segcore/Utils.cpp
@@ -25,7 +25,7 @@ ParsePksFromFieldData(std::vector<PkType>& pks, const DataArray& data) {
             break;
         }
         case DataType::VARCHAR: {
-            auto src_data = data.scalars().string_data().data();
+            auto& src_data = data.scalars().string_data().data();
             std::copy(src_data.begin(), src_data.end(), pks.begin());
             break;
         }
@@ -47,7 +47,7 @@ ParsePksFromIDs(std::vector<PkType>& pks,
             break;
         }
         case DataType::VARCHAR: {
-            auto source_data = data.str_id().data();
+            auto& source_data = data.str_id().data();
             std::copy(source_data.begin(), source_data.end(), pks.begin());
             break;
         }
@@ -363,7 +363,7 @@ MergeDataArray(
                 continue;
             }
             case DataType::VARCHAR: {
-                auto data = src_field_data->scalars().string_data();
+                auto& data = src_field_data->scalars().string_data();
                 auto obj = scalar_array->mutable_string_data();
                 *(obj->mutable_data()->Add()) = data.data(src_offset);
                 continue;