dont't reuse allocator until prefetch.end

src/storage/blocksstable/index_block/ob_ddl_index_block_row_iterator.cpp

@@ -721,8 +721,9 @@ int ObDDLSStableAllRangeIterator::get_index_row_count(const ObDatumRange &range,
     bool tmp_reach_cursor_end = false;
     ObMicroIndexRowItem tmp_index_item;
     int64_t tmp_row_offset = 0;
+    ObArenaAllocator idx_row_allocator("DDL_Row_Cnt", OB_MALLOC_NORMAL_BLOCK_SIZE, MTL_ID());
     while (OB_SUCC(ret)) {
-      if (OB_FAIL(tmp_index_macro_iter.get_next_idx_row(idx_row_allocator_, tmp_index_item, tmp_row_offset, tmp_reach_cursor_end))) {
+      if (OB_FAIL(tmp_index_macro_iter.get_next_idx_row(idx_row_allocator, tmp_index_item, tmp_row_offset, tmp_reach_cursor_end))) {
         if (OB_ITER_END != ret) {
         LOG_WARN("fail to get next idx info", K(ret), K(tmp_index_item), K(tmp_reach_cursor_end), K(tmp_index_macro_iter));
         } else {
@@ -736,6 +737,8 @@ int ObDDLSStableAllRangeIterator::get_index_row_count(const ObDatumRange &range,
     if (OB_FAIL(ret)) {
       index_row_count = 0;
     }
+    tmp_index_item.reset();
+    idx_row_allocator.reset();
   }
   return ret;
 }

src/storage/blocksstable/index_block/ob_index_block_macro_iterator.cpp

@@ -48,9 +48,17 @@ int ObMicroIndexRowItem::init(ObIAllocator &allocator,
     LOG_WARN("invalid arguemen", K(ret), KP(idx_row_header), KP(endkey), KP(idx_minor_info), KP(agg_row_buf));
   } else {
     allocator_ = &allocator;
-    endkey_ = endkey; // already deep_copied outside
     agg_buf_size_ = agg_buf_size;
 
+    void *key_buf = nullptr;
+    if (OB_ISNULL(key_buf = allocator_->alloc(sizeof(ObDatumRowkey)))) {
+      ret = OB_ALLOCATE_MEMORY_FAILED;
+      LOG_WARN("allocate memory failed", K(ret), K(sizeof(ObDatumRowkey)));
+    } else if (FALSE_IT(endkey_ = new (key_buf) ObDatumRowkey())) {
+    } else if (OB_FAIL(endkey->deep_copy(*endkey_, allocator))) {
+      LOG_WARN("fail to deep copy rowkey", K(ret), KPC(endkey_), KPC(endkey));
+    }
+
     void *header_buf = nullptr;
     if (OB_ISNULL(header_buf = allocator_->alloc(sizeof(ObIndexBlockRowHeader)))) {
       ret = OB_ALLOCATE_MEMORY_FAILED;
@@ -86,9 +94,13 @@ int ObMicroIndexRowItem::init(ObIAllocator &allocator,
 void ObMicroIndexRowItem::reset()
 {
   int ret = OB_SUCCESS;
-  endkey_ = nullptr;
   agg_buf_size_ = 0;
   if (OB_NOT_NULL(allocator_)) {
+    if (OB_NOT_NULL(endkey_)){
+      endkey_->~ObDatumRowkey();
+      allocator_->free(endkey_);
+      endkey_ = nullptr;
+    }
     if (OB_NOT_NULL(idx_row_header_)){
       idx_row_header_->~ObIndexBlockRowHeader();
       allocator_->free(idx_row_header_);
@@ -107,6 +119,17 @@ void ObMicroIndexRowItem::reset()
   allocator_ = nullptr;
 }
 
+void ObMicroIndexRowItem::reuse()
+{
+  int ret = OB_SUCCESS;
+  endkey_ = nullptr;
+  agg_buf_size_ = 0;
+  idx_row_header_ = nullptr;
+  idx_minor_info_ = nullptr;
+  agg_row_buf_ = nullptr;
+  allocator_ = nullptr;
+}
+
 ObIndexBlockMacroIterator::ObIndexBlockMacroIterator()
   : sstable_(nullptr), iter_range_(nullptr),
     tree_cursor_(), allocator_(nullptr),
@@ -361,8 +384,7 @@ int ObIndexBlockMacroIterator::get_next_idx_row(ObIAllocator &item_allocator, Ob
       LOG_WARN("Fail to get current endkey", K(ret), K_(tree_cursor));
     } else if (OB_FAIL(deep_copy_rowkey(rowkey, curr_key_, curr_key_buf_))) {
       STORAGE_LOG(WARN, "Failed to save curr key", K(ret), K(rowkey));
-    } else if (FALSE_IT(macro_index_item.reset())) {
+    } else if (FALSE_IT(macro_index_item.reuse())) {
-    } else if (FALSE_IT(item_allocator.reuse())) {
     } else if (OB_FAIL(macro_index_item.init(item_allocator, idx_row_header, &curr_key_, minor_meta_info, agg_row_buf, agg_buf_size))) {
       STORAGE_LOG(WARN, "Failed to init macro index item", K(ret), K(macro_index_item));
     } else if (OB_FAIL(tree_cursor_.move_forward(is_reverse_scan_))) {

src/storage/blocksstable/index_block/ob_index_block_macro_iterator.h

@@ -80,11 +80,12 @@ public:
             const char *agg_row_buf,
             const int64_t agg_buf_size);
   void reset();
+  void reuse();
   TO_STRING_KV(KPC(idx_row_header_), KPC(endkey_), KPC(idx_minor_info_), K(agg_row_buf_), K(agg_buf_size_), KP(allocator_));
 
 public:
   ObIAllocator *allocator_;
-  const blocksstable::ObDatumRowkey *endkey_;
+  blocksstable::ObDatumRowkey *endkey_;
   ObIndexBlockRowHeader *idx_row_header_;
   ObIndexBlockRowMinorMetaInfo *idx_minor_info_;
   char *agg_row_buf_; //max 1024