SERVER-46699 Report the oplog visibility timestamp in FTDC

(cherry picked from commit 454e1823bbbe7cc25d6f34856913d8161d729e4b)

3 files changed, 8 insertions, 2 deletions

diff --git a/src/mongo/bson/timestamp.h b/src/mongo/bson/timestamp.h
index 231f42e422d..b876001e7c2 100644
--- a/src/mongo/bson/timestamp.h
+++ b/src/mongo/bson/timestamp.h
@@ -64,7 +64,7 @@ public:
     explicit Timestamp(Date_t date) : Timestamp(date.toULL()) {}
 
     /**
-     * DEPRECATED Constructor that builds a Timestamp from a 64-bit unsigned integer by using
+     * Constructor that builds a Timestamp from a 64-bit unsigned integer by using
      * the high-order 4 bytes of "v" for the "secs" field and the low-order 4 bytes for the "i"
      * field.
      */
diff --git a/src/mongo/db/storage/wiredtiger/wiredtiger_oplog_manager.h b/src/mongo/db/storage/wiredtiger/wiredtiger_oplog_manager.h
index 2e35cce5353..5c6bb356b17 100644
--- a/src/mongo/db/storage/wiredtiger/wiredtiger_oplog_manager.h
+++ b/src/mongo/db/storage/wiredtiger/wiredtiger_oplog_manager.h
@@ -111,6 +111,6 @@ private:
     // journal flushing should not be delayed.
     std::int64_t _opsWaitingForVisibility = 0;  // Guarded by oplogVisibilityStateMutex.
 
-    AtomicUInt64 _oplogReadTimestamp;
+    AtomicUInt64 _oplogReadTimestamp{0};
 };
 }  // namespace mongo
diff --git a/src/mongo/db/storage/wiredtiger/wiredtiger_server_status.cpp b/src/mongo/db/storage/wiredtiger/wiredtiger_server_status.cpp
index 6e17530982e..34e4f314c9b 100644
--- a/src/mongo/db/storage/wiredtiger/wiredtiger_server_status.cpp
+++ b/src/mongo/db/storage/wiredtiger/wiredtiger_server_status.cpp
@@ -83,6 +83,12 @@ BSONObj WiredTigerServerStatusSection::generateSection(OperationContext* opCtx,
 
     WiredTigerKVEngine::appendGlobalStats(bob);
 
+    {
+        BSONObjBuilder subsection(bob.subobjStart("oplog"));
+        subsection.append("visibility timestamp",
+                          Timestamp(_engine->getOplogManager()->getOplogReadTimestamp()));
+    }
+
     return bob.obj();
 }