From 2acfa1137c51fe4fffc800c7e7cf0d5402de836e Mon Sep 17 00:00:00 2001
From: Fengjingkun <dlutfjk@163.com>
Date: Mon, 29 May 2023 04:11:49 +0000
Subject: [PATCH] [CP] fix bug about update memtables in table store

---
 src/storage/tablet/ob_table_store_util.cpp   | 15 +++++++++++----
 src/storage/tablet/ob_table_store_util.h     |  2 +-
 src/storage/tablet/ob_tablet_table_store.cpp |  2 +-
 3 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/src/storage/tablet/ob_table_store_util.cpp b/src/storage/tablet/ob_table_store_util.cpp
index c291befc32..b32a870040 100644
--- a/src/storage/tablet/ob_table_store_util.cpp
+++ b/src/storage/tablet/ob_table_store_util.cpp
@@ -584,7 +584,9 @@ int ObMemtableArray::build(
   return ret;
 }
 
-int ObMemtableArray::rebuild(common::ObIArray<ObTableHandleV2> &handle_array)
+int ObMemtableArray::rebuild(
+    const share::SCN &clog_checkpoint_scn,
+    common::ObIArray<ObTableHandleV2> &handle_array)
 {
   int ret = OB_SUCCESS;
 
@@ -593,7 +595,9 @@ int ObMemtableArray::rebuild(common::ObIArray<ObTableHandleV2> &handle_array)
     LOG_ERROR("ObMemtableArray not inited", K(ret), KPC(this), K(handle_array));
   } else {
     ObITable *last_memtable = get_table(count() - 1);
-    SCN end_scn = (NULL == last_memtable) ? SCN::min_scn() : last_memtable->get_end_scn();
+    SCN last_memtable_end_scn = (NULL == last_memtable)
+                              ? clog_checkpoint_scn // memtable was filtered when tablet was initialized, use ckpt scn to filter again
+                              : last_memtable->get_end_scn();
 
     for (int64_t i = 0; OB_SUCC(ret) && i < handle_array.count(); ++i) {
       memtable::ObMemtable *memtable = nullptr;
@@ -604,8 +608,11 @@ int ObMemtableArray::rebuild(common::ObIArray<ObTableHandleV2> &handle_array)
       } else if (FALSE_IT(memtable = reinterpret_cast<memtable::ObMemtable *>(table))) {
       } else if (memtable->is_empty()) {
         FLOG_INFO("Empty memtable discarded", KPC(memtable));
-      } else if (table->get_end_scn() < end_scn) {
-      } else if (table->get_end_scn() == end_scn && table == last_memtable) { //fix issue 41996395
+      } else if (memtable->get_end_scn() == last_memtable_end_scn && memtable == last_memtable) {
+        // fix issue 41996395
+        // if last memtable is freezing, its end scn may still be INT64_MAX, which will cause the new active memtable to be filtered.
+        continue;
+      } else if (memtable->get_end_scn() <= last_memtable_end_scn) {
       } else if (OB_FAIL(add_table(table))) {
         LOG_WARN("failed to add memtable to curr memtables", K(ret), KPC(this));
       }
diff --git a/src/storage/tablet/ob_table_store_util.h b/src/storage/tablet/ob_table_store_util.h
index f8c69ecdc4..6cf530b040 100644
--- a/src/storage/tablet/ob_table_store_util.h
+++ b/src/storage/tablet/ob_table_store_util.h
@@ -111,7 +111,7 @@ public:
   int init(common::ObIAllocator *allocator);
   int init(common::ObIAllocator *allocator, const ObMemtableArray &other);
   int build(common::ObIArray<ObTableHandleV2> &handle_array, const int64_t start_pos = 0);
-  int rebuild(common::ObIArray<ObTableHandleV2> &handle_array);
+  int rebuild(const share::SCN &clog_checkpoint_scn, common::ObIArray<ObTableHandleV2> &handle_array);
   int prepare_allocate();
   int find(const ObITable::TableKey &table_key, ObTableHandleV2 &handle) const;
   int find(const share::SCN &start_scn, const int64_t base_version, ObITable *&table, int64_t &mem_pos) const;
diff --git a/src/storage/tablet/ob_tablet_table_store.cpp b/src/storage/tablet/ob_tablet_table_store.cpp
index 6c997507df..208c37fe82 100644
--- a/src/storage/tablet/ob_tablet_table_store.cpp
+++ b/src/storage/tablet/ob_tablet_table_store.cpp
@@ -440,7 +440,7 @@ int ObTabletTableStore::update_memtables()
   } else if (OB_FAIL(tablet_ptr_->get_memtable_mgr()->get_all_memtables(inc_memtables))) {
     LOG_WARN("failed to get all memtables from memtable_mgr", K(ret));
   } else if (FALSE_IT(time_guard.click("get_all_memtable"))) {
-  } else if (OB_FAIL(memtables_.rebuild(inc_memtables))) {
+  } else if (OB_FAIL(memtables_.rebuild(tablet_ptr_->get_clog_checkpoint_scn(), inc_memtables))) {
     LOG_ERROR("failed to rebuild table store memtables", K(ret), K(inc_memtables), KPC(this));
   } else if (FALSE_IT(time_guard.click("memtables_.rebuild"))) {
   } else {