MB-41985: Set 'persistenceSeqno' when vbucket has rolled back

The persistence seqno after rollback was still left at the
pre-rollback (future value).

Change-Id: Ia9deebb6c0b6f099d793ed7968da9f82d560e630
Reviewed-on: http://review.couchbase.org/c/kv_engine/+/137943
Tested-by: Jim Walker <[email protected]>
Reviewed-by: Dave Rigby <[email protected]>

Author: jimwwalker

engines/ep/src/kv_bucket.cc

@@ -2489,12 +2489,10 @@ TaskStatus KVBucket::rollback(Vbid vbid, uint64_t rollbackSeqno) {
                                         */) {
                 rollbackUnpersistedItems(*vb, result.highSeqno);
                 loadPreparedSyncWrites(wlh, *vb);
-                vb->postProcessRollback(result, prevHighSeqno);
-
-                // And update collections post rollback
-                vb->collectionsRolledBack(
-                        *vbMap.getShardByVbId(vbid)->getROUnderlying());
-
+                vb->postProcessRollback(
+                        result,
+                        prevHighSeqno,
+                        *vbMap.getShardByVbId(vbid)->getRWUnderlying());
                 engine.getDcpConnMap().closeStreamsDueToRollback(vbid);
                 return TaskStatus::Complete;
             }

engines/ep/src/vbucket.cc

@@ -3052,14 +3052,19 @@ bool VBucket::removeItemFromMemory(const Item& item) {
 }
 
 void VBucket::postProcessRollback(const RollbackResult& rollbackResult,
-                                  uint64_t prevHighSeqno) {
+                                  uint64_t prevHighSeqno,
+                                  KVStore& kvstore) {
     failovers->pruneEntries(rollbackResult.highSeqno);
     checkpointManager->clear(*this, rollbackResult.highSeqno);
     setPersistedSnapshot(
             {rollbackResult.snapStartSeqno, rollbackResult.snapEndSeqno});
     incrRollbackItemCount(prevHighSeqno - rollbackResult.highSeqno);
     checkpointManager->setOpenCheckpointId(1);
     setReceivingInitialDiskSnapshot(false);
+    setPersistenceSeqno(kvstore.getLastPersistedSeqno(getId()));
+
+    // And update collections post rollback
+    collectionsRolledBack(kvstore);
 }
 
 void VBucket::collectionsRolledBack(KVStore& kvstore) {
@@ -3174,7 +3179,7 @@ void VBucket::_addStats(VBucketStatsDetailLevel detail,
                 checkpointManager->getMaxVisibleSeqno(),
                 add_stat,
                 c);
-
+        addStat("persistence_seqno", getPersistenceSeqno(), add_stat, c);
         hlc.addStats(statPrefix, add_stat, c);
     }
         // fallthrough

engines/ep/src/vbucket.h

@@ -1488,16 +1488,11 @@ class VBucket : public std::enable_shared_from_this<VBucket> {
      *                       snapshot end seqno of the last snapshot in the
      *                       vBucket after the rollback
      * @param prevHighSeqno high seqno before the rollback
-     */
-    void postProcessRollback(const RollbackResult& rollbackResult,
-                             uint64_t prevHighSeqno);
-
-    /**
-     * Update collections following a rollback
-     *
      * @param kvstore A KVStore that is used for retrieving stored metadata
      */
-    void collectionsRolledBack(KVStore& kvstore);
+    void postProcessRollback(const RollbackResult& rollbackResult,
+                             uint64_t prevHighSeqno,
+                             KVStore& kvstore);
 
     /**
      * Debug - print a textual description of the VBucket to stderr.
@@ -2050,6 +2045,13 @@ class VBucket : public std::enable_shared_from_this<VBucket> {
             UseActiveVBMemThreshold useActiveVBMemThrehsold =
                     UseActiveVBMemThreshold::No);
 
+    /**
+     * Update collections following a rollback
+     *
+     * @param kvstore A KVStore that is used for retrieving stored metadata
+     */
+    void collectionsRolledBack(KVStore& kvstore);
+
     void _addStats(VBucketStatsDetailLevel detail,
                    const AddStatFn& add_stat,
                    const void* c);

engines/ep/tests/ep_testsuite.cc

@@ -6875,6 +6875,7 @@ static enum test_result test_mb19687_fixed(EngineIface* h) {
               "vb_0:ops_reject",
               "vb_0:ops_update",
               "vb_0:pending_writes",
+              "vb_0:persistence_seqno",
               "vb_0:purge_seqno",
               "vb_0:queue_age",
               "vb_0:queue_drain",

engines/ep/tests/module_tests/evp_store_rollback_test.cc

@@ -540,6 +540,8 @@ class RollbackTest
                       store->getVBucket(vbid)->getHighSeqno());
         }
         EXPECT_EQ(0, store->getVBucket(vbid)->ht.getNumSystemItems());
+        EXPECT_EQ(store->getVBucket(vbid)->getHighSeqno(),
+                  store->getVBucket(vbid)->getPersistenceSeqno());
     }
 
     void rollback_to_zero(int64_t rollbackSeqno) {
@@ -577,6 +579,7 @@ class RollbackTest
                           .lock()
                           .getPersistedHighSeqno(CollectionID::Default));
         EXPECT_EQ(0, store->getVBucket(vbid)->getNumItems());
+        EXPECT_EQ(0, store->getVBucket(vbid)->getPersistenceSeqno());
     }
 
 protected: