SERVER-50915 fsyncLock must not take a stable checkpoint when majority read concern is off

4 files changed, 8 insertions, 6 deletions

diff --git a/src/mongo/db/repl/replication_recovery.cpp b/src/mongo/db/repl/replication_recovery.cpp
index 3b1f1ca9c87..fc66c03da01 100644
--- a/src/mongo/db/repl/replication_recovery.cpp
+++ b/src/mongo/db/repl/replication_recovery.cpp
@@ -330,9 +330,7 @@ void ReplicationRecoveryImpl::_recoverFromUnstableCheckpoint(OperationContext* o
     // datafiles contain any writes that were taken before the crash.
     _consistencyMarkers->setAppliedThrough(opCtx, topOfOplog);
 
-    // Force the set `appliedThrough` to become durable on disk in a checkpoint. This method would
-    // typically take a stable checkpoint, but because we're starting up from a checkpoint that
-    // has no checkpoint timestamp, the stable checkpoint "degrades" into an unstable checkpoint.
+    // Force the set `appliedThrough` to become durable on disk in a checkpoint.
     //
     // Not waiting for checkpoint durability here can result in a scenario where the node takes
     // writes and persists them to the oplog, but crashes before a stable checkpoint persists a
diff --git a/src/mongo/db/storage/wiredtiger/wiredtiger_kv_engine.cpp b/src/mongo/db/storage/wiredtiger/wiredtiger_kv_engine.cpp
index 5fc2d6ad474..e80512e63fc 100644
--- a/src/mongo/db/storage/wiredtiger/wiredtiger_kv_engine.cpp
+++ b/src/mongo/db/storage/wiredtiger/wiredtiger_kv_engine.cpp
@@ -939,8 +939,8 @@ int WiredTigerKVEngine::flushAllFiles(OperationContext* opCtx, bool sync) {
     }
     syncSizeInfo(false);
     const bool forceCheckpoint = true;
-    // If there's no journal, we must take a full checkpoint.
-    const bool stableCheckpoint = _durable;
+    // If there's no journal or if majority read concern is off, we must take a full checkpoint.
+    const bool stableCheckpoint = _durable && serverGlobalParams.enableMajorityReadConcern;
     _sessionCache->waitUntilDurable(forceCheckpoint, stableCheckpoint);
 
     return 1;
diff --git a/src/mongo/db/storage/wiredtiger/wiredtiger_recovery_unit.cpp b/src/mongo/db/storage/wiredtiger/wiredtiger_recovery_unit.cpp
index 1adbcfcc530..7ec4e21c916 100644
--- a/src/mongo/db/storage/wiredtiger/wiredtiger_recovery_unit.cpp
+++ b/src/mongo/db/storage/wiredtiger/wiredtiger_recovery_unit.cpp
@@ -288,7 +288,7 @@ bool WiredTigerRecoveryUnit::waitUntilDurable() {
 bool WiredTigerRecoveryUnit::waitUntilUnjournaledWritesDurable() {
     invariant(!_inUnitOfWork);
     const bool forceCheckpoint = true;
-    const bool stableCheckpoint = true;
+    const bool stableCheckpoint = serverGlobalParams.enableMajorityReadConcern;
     // Calling `waitUntilDurable` with `forceCheckpoint` set to false only performs a log
     // (journal) flush, and thus has no effect on unjournaled writes. Setting `forceCheckpoint` to
     // true will lock in stable writes to unjournaled tables.
diff --git a/src/mongo/db/storage/wiredtiger/wiredtiger_session_cache.cpp b/src/mongo/db/storage/wiredtiger/wiredtiger_session_cache.cpp
index 1e885814cf3..8219cf91808 100644
--- a/src/mongo/db/storage/wiredtiger/wiredtiger_session_cache.cpp
+++ b/src/mongo/db/storage/wiredtiger/wiredtiger_session_cache.cpp
@@ -244,6 +244,10 @@ void WiredTigerSessionCache::waitUntilDurable(bool forceCheckpoint, bool stableC
         return;
     }
 
+    if (stableCheckpoint) {
+        invariant(serverGlobalParams.enableMajorityReadConcern);
+    }
+
     const int shuttingDown = _shuttingDown.fetchAndAdd(1);
     ON_BLOCK_EXIT([this] { _shuttingDown.fetchAndSubtract(1); });