[CP] Fix rescan hold macro handle too long

src/storage/access/ob_index_tree_prefetcher.cpp

@@ -29,6 +29,7 @@ void ObIndexTreePrefetcher::reset()
 {
   is_inited_ = false;
   is_rescan_ = false;
+  rescan_cnt_ = 0;
   data_version_ = 0;
   sstable_ = nullptr;
   data_block_cache_ = nullptr;
@@ -108,6 +109,14 @@ int ObIndexTreePrefetcher::switch_context(
       if (OB_FAIL(micro_block_handle_mgr_.init(true, false, *access_ctx.stmt_allocator_))) {
         LOG_WARN("failed to init block handle mgr", K(ret));
       }
+    } else {
+      rescan_cnt_++;
+      if (rescan_cnt_ >= MAX_RESCAN_HOLD_LIMIT) {
+        rescan_cnt_ = 0;
+        if (OB_FAIL(micro_block_handle_mgr_.reset_handle_cache())) {
+          STORAGE_LOG(WARN, "failed to reset handle cache", K(ret));
+        }
+      }
     }
   }
   return ret;
@@ -483,6 +492,14 @@ int ObIndexTreeMultiPrefetcher::switch_context(
       if (OB_FAIL(micro_block_handle_mgr_.init(true, false, *access_ctx.stmt_allocator_))) {
         LOG_WARN("failed to init block handle mgr", K(ret));
       }
+    } else {
+      rescan_cnt_++;
+      if (rescan_cnt_ >= MAX_RESCAN_HOLD_LIMIT) {
+        rescan_cnt_ = 0;
+        if (OB_FAIL(micro_block_handle_mgr_.reset_handle_cache())) {
+          STORAGE_LOG(WARN, "failed to reset handle cache", K(ret));
+        }
+      }
     }
     if (OB_SUCC(ret)) {
       if (index_scanner_.is_valid()) {

src/storage/access/ob_index_tree_prefetcher.h

@@ -115,6 +115,7 @@ public:
   ObIndexTreePrefetcher() :
       is_inited_(false),
       is_rescan_(false),
+      rescan_cnt_(0),
       data_version_(0),
       sstable_(nullptr),
       data_block_cache_(nullptr),
@@ -172,8 +173,10 @@ private:
   }
 
 protected:
+  static const int64_t MAX_RESCAN_HOLD_LIMIT = 64;
   bool is_inited_;
   bool is_rescan_;
+  int64_t rescan_cnt_;
   int64_t data_version_;
   ObSSTable *sstable_;
   ObDataMicroBlockCache *data_block_cache_;

src/storage/ob_handle_cache.h

@@ -57,6 +57,15 @@ public:
 
   virtual ~ObHandleCache() {}
 
+  void reset_handles()
+  {
+    for (int64_t i = 0; i < N; ++i) {
+      nodes_[i].reset();
+    }
+    MEMSET(buckets_, -1, sizeof(buckets_));
+    MEMSET(chain_, -1, sizeof(chain_));
+  }
+
   int get_handle(const Key &key, Handle &handle)
   {
     int ret = common::OB_SUCCESS;

src/storage/ob_micro_block_handle_mgr.cpp

@@ -333,5 +333,21 @@ int ObMicroBlockHandleMgr::put_micro_block_handle(
   return ret;
 }
 
+int ObMicroBlockHandleMgr::reset_handle_cache()
+{
+  int ret = OB_SUCCESS;
+  if (IS_NOT_INIT) {
+    ret = OB_NOT_INIT;
+    STORAGE_LOG(WARN, "block handle mgr is not inited", K(ret));
+  } else if (is_multi_) {
+    if (is_ordered_) {
+      last_handle_->reset();
+    } else {
+      handle_cache_->reset_handles();
+    }
+  }
+  return ret;
+}
+
 }
 }

src/storage/ob_micro_block_handle_mgr.h

@@ -87,6 +87,7 @@ public:
       const blocksstable::MacroBlockId &macro_id,
       const blocksstable::ObIndexBlockRowHeader &idx_header,
       ObMicroBlockDataHandle &micro_block_handle);
+  int reset_handle_cache();
 private:
   // allocator for index micro block prefetch failed and async io
   common::ObFIFOAllocator allocator_;