SERVER-40337: Remove oldestOpenUnpreparedReadTimestamp from serverStatus.transactions

This reverts most of the work done in 3bb72042c29ceac96ec628ee643cbc4db8e982ab

3 files changed, 3 insertions, 22 deletions

diff --git a/src/mongo/db/server_transactions_metrics.cpp b/src/mongo/db/server_transactions_metrics.cpp
index 54300a1ca26..1daa320782d 100644
--- a/src/mongo/db/server_transactions_metrics.cpp
+++ b/src/mongo/db/server_transactions_metrics.cpp
@@ -149,15 +149,7 @@ void ServerTransactionsMetrics::decrementCurrentPrepared() {
     _currentPrepared.fetchAndSubtract(1);
 }
 
-Timestamp ServerTransactionsMetrics::_getOldestOpenUnpreparedReadTimestamp(
-    OperationContext* opCtx) {
-    // The history is not pinned in memory once a transaction has been prepared since reads
-    // are no longer possible. Therefore, the timestamp returned by the storage engine refers
-    // to the oldest read timestamp for any open unprepared transaction.
-    return opCtx->getServiceContext()->getStorageEngine()->getOldestOpenReadTimestamp();
-}
-
-void ServerTransactionsMetrics::updateStats(TransactionsStats* stats, OperationContext* opCtx) {
+void ServerTransactionsMetrics::updateStats(TransactionsStats* stats) {
     stats->setCurrentActive(_currentActive.load());
     stats->setCurrentInactive(_currentInactive.load());
     stats->setCurrentOpen(_currentOpen.load());
@@ -168,8 +160,6 @@ void ServerTransactionsMetrics::updateStats(TransactionsStats* stats, OperationC
     stats->setTotalPreparedThenCommitted(_totalPreparedThenCommitted.load());
     stats->setTotalPreparedThenAborted(_totalPreparedThenAborted.load());
     stats->setCurrentPrepared(_currentPrepared.load());
-    stats->setOldestOpenUnpreparedReadTimestamp(
-        ServerTransactionsMetrics::_getOldestOpenUnpreparedReadTimestamp(opCtx));
 }
 
 namespace {
@@ -192,7 +182,7 @@ public:
         // lifecycle within a session. Both are assigned transaction numbers, and so both are often
         // referred to as “transactions”.
         RetryableWritesStats::get(opCtx)->updateStats(&stats);
-        ServerTransactionsMetrics::get(opCtx)->updateStats(&stats, opCtx);
+        ServerTransactionsMetrics::get(opCtx)->updateStats(&stats);
         return stats.toBSON();
     }
 
diff --git a/src/mongo/db/server_transactions_metrics.h b/src/mongo/db/server_transactions_metrics.h
index d5b829f6845..250b2c41931 100644
--- a/src/mongo/db/server_transactions_metrics.h
+++ b/src/mongo/db/server_transactions_metrics.h
@@ -90,16 +90,9 @@ public:
     /**
      * Appends the accumulated stats to a transactions stats object.
      */
-    void updateStats(TransactionsStats* stats, OperationContext* opCtx);
+    void updateStats(TransactionsStats* stats);
 
 private:
-    /**
-     * Returns the oldest read timestamp in use by any open unprepared transaction. This will
-     * return a null timestamp if there is no oldest open unprepared read timestamp to be
-     * returned.
-     */
-    static Timestamp _getOldestOpenUnpreparedReadTimestamp(OperationContext* opCtx);
-
     // The number of multi-document transactions currently active.
     AtomicWord<unsigned long long> _currentActive{0};
 
diff --git a/src/mongo/db/transactions_stats.idl b/src/mongo/db/transactions_stats.idl
index ad70e141d6f..c2a269d4a79 100644
--- a/src/mongo/db/transactions_stats.idl
+++ b/src/mongo/db/transactions_stats.idl
@@ -83,5 +83,3 @@ structs:
       currentPrepared:
         type: long
         default: 0
-      oldestOpenUnpreparedReadTimestamp:
-        type: timestamp