avoid init useless DeltaMergeStore (#5705)

ref #5665
pingcap · Aug 26, 2022 · b109a12 · b109a12
1 parent 61e436b
commit b109a12
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Showing 4 changed files with 23 additions and 12 deletions.
diff --git a/dbms/src/Interpreters/AsynchronousMetrics.cpp b/dbms/src/Interpreters/AsynchronousMetrics.cpp
@@ -177,11 +177,14 @@ void AsynchronousMetrics::update()
 
                 if (auto dt_storage = std::dynamic_pointer_cast<StorageDeltaMerge>(table); dt_storage)
                 {
-                    auto stat = dt_storage->getStore()->getStat();
-                    calculateMax(max_dt_stable_oldest_snapshot_lifetime, stat.storage_stable_oldest_snapshot_lifetime);
-                    calculateMax(max_dt_delta_oldest_snapshot_lifetime, stat.storage_delta_oldest_snapshot_lifetime);
-                    calculateMax(max_dt_meta_oldest_snapshot_lifetime, stat.storage_meta_oldest_snapshot_lifetime);
-                    calculateMax(max_dt_background_tasks_length, stat.background_tasks_length);
+                    if (auto store = dt_storage->getStoreIfInited(); store)
+                    {
+                        auto stat = store->getStat();
+                        calculateMax(max_dt_stable_oldest_snapshot_lifetime, stat.storage_stable_oldest_snapshot_lifetime);
+                        calculateMax(max_dt_delta_oldest_snapshot_lifetime, stat.storage_delta_oldest_snapshot_lifetime);
+                        calculateMax(max_dt_meta_oldest_snapshot_lifetime, stat.storage_meta_oldest_snapshot_lifetime);
+                        calculateMax(max_dt_background_tasks_length, stat.background_tasks_length);
+                    }
                 }
             }
         }

diff --git a/dbms/src/Storages/Page/V3/BlobStore.cpp b/dbms/src/Storages/Page/V3/BlobStore.cpp
@@ -982,13 +982,10 @@ std::vector<BlobFileId> BlobStore::getGCStats()
             // Avoid divide by zero
             if (right_margin == 0)
             {
-                if (unlikely(stat->sm_valid_rate != 0))
-                {
-                    throw Exception(fmt::format("Current blob is empty, but valid rate is not 0. [blob_id={}][valid_size={}][valid_rate={}]",
-                                                stat->id,
-                                                stat->sm_valid_size,
-                                                stat->sm_valid_rate));
-                }
+                // Note `stat->sm_total_size` isn't strictly the same as the actual size of underlying BlobFile after restart tiflash,
+                // because some entry may be deleted but the actual disk space is not reclaimed in previous run.
+                // TODO: avoid always truncate on empty BlobFile
+                RUNTIME_CHECK_MSG(stat->sm_valid_size == 0, "Current blob is empty, but valid size is not 0. [blob_id={}] [valid_size={}] [valid_rate={}]", stat->id, stat->sm_valid_size, stat->sm_valid_rate);
 
                 // If current blob empty, the size of in disk blob may not empty
                 // So we need truncate current blob, and let it be reused.

diff --git a/dbms/src/Storages/StorageDeltaMerge.cpp b/dbms/src/Storages/StorageDeltaMerge.cpp
@@ -906,6 +906,15 @@ void StorageDeltaMerge::deleteRows(const Context & context, size_t delete_rows)
         LOG_FMT_ERROR(log, "Rows after delete range not match, expected: {}, got: {}", (total_rows - delete_rows), after_delete_rows);
 }
 
+DM::DeltaMergeStorePtr StorageDeltaMerge::getStoreIfInited()
+{
+    if (storeInited())
+    {
+        return _store;
+    }
+    return nullptr;
+}
+
 std::pair<DB::DecodingStorageSchemaSnapshotConstPtr, BlockUPtr> StorageDeltaMerge::getSchemaSnapshotAndBlockForDecoding(const TableStructureLockHolder & table_structure_lock, bool need_block)
 {
     (void)table_structure_lock;

diff --git a/dbms/src/Storages/StorageDeltaMerge.h b/dbms/src/Storages/StorageDeltaMerge.h
@@ -147,6 +147,8 @@ class StorageDeltaMerge
         return getAndMaybeInitStore();
     }
 
+    DM::DeltaMergeStorePtr getStoreIfInited();
+
     bool isCommonHandle() const override { return is_common_handle; }
 
     size_t getRowKeyColumnSize() const override { return rowkey_column_size; }