diff --git a/fdbserver/BackupWorker.actor.cpp b/fdbserver/BackupWorker.actor.cpp
index c2587eb905..177aa41e65 100644
--- a/fdbserver/BackupWorker.actor.cpp
+++ b/fdbserver/BackupWorker.actor.cpp
@@ -72,6 +72,7 @@ struct BackupData {
 	const Optional<Version> endVersion; // old epoch's end version (inclusive), or empty for current epoch
 	const LogEpoch recruitedEpoch;
 	const LogEpoch backupEpoch;
+	LogEpoch oldestBackupEpoch = 0;
 	Version minKnownCommittedVersion;
 	Version savedVersion;
 	AsyncVar<Reference<ILogSystem>> logSystem;
@@ -169,13 +170,12 @@ struct BackupData {
 	}
 
 	void pop() {
-		const LogEpoch oldest = logSystem.get()->getOldestBackupEpoch();
-		if (backupEpoch > oldest) {
+		if (backupEpoch > oldestBackupEpoch) {
 			// Defer pop if old epoch hasn't finished popping yet.
 			TraceEvent("BackupWorkerPopDeferred", myId)
 			    .suppressFor(1.0)
 			    .detail("BackupEpoch", backupEpoch)
-			    .detail("OldestEpoch", oldest)
+			    .detail("OldestEpoch", oldestBackupEpoch)
 			    .detail("Version", savedVersion);
 			return;
 		}
@@ -552,6 +552,14 @@ ACTOR Future<Void> saveMutationsToFile(BackupData* self, Version popVersion, int
 		MutationRef m;
 		if (!message.isBackupMessage(&m)) continue;
 
+		if (debugMutation("addMutation", message.version.version, m)) {
+			TraceEvent("BackupWorkerDebug", self->myId)
+			    .detail("Version", message.version.toString())
+			    .detail("Mutation", m.toString())
+			    .detail("KCV", self->minKnownCommittedVersion)
+			    .detail("SavedVersion", self->savedVersion);
+		}
+
 		std::vector<Future<Void>> adds;
 		if (m.type != MutationRef::Type::ClearRange) {
 			for (int index : keyRangeMap[m.param1]) {
@@ -804,15 +812,14 @@ ACTOR Future<Void> backupWorker(BackupInterface interf, InitializeBackupRequest
 				dbInfoChange = db->onChange();
 				Reference<ILogSystem> ls = ILogSystem::fromServerDBInfo(self.myId, db->get(), true);
 				bool hasPseudoLocality = ls.isValid() && ls->hasPseudoLocality(tagLocalityBackup);
-				LogEpoch oldestBackupEpoch = 0;
 				if (hasPseudoLocality) {
 					self.logSystem.set(ls);
 					self.pop();
-					oldestBackupEpoch = ls->getOldestBackupEpoch();
+					self.oldestBackupEpoch = std::max(self.oldestBackupEpoch, ls->getOldestBackupEpoch());
 				}
 				TraceEvent("BackupWorkerLogSystem", self.myId)
 				    .detail("HasBackupLocality", hasPseudoLocality)
-				    .detail("OldestBackupEpoch", oldestBackupEpoch)
+				    .detail("OldestBackupEpoch", self.oldestBackupEpoch)
 				    .detail("Tag", self.tag.toString());
 			}
 			when(wait(done)) {
diff --git a/fdbserver/ClusterController.actor.cpp b/fdbserver/ClusterController.actor.cpp
index 28648fbd10..fc00bccbf0 100644
--- a/fdbserver/ClusterController.actor.cpp
+++ b/fdbserver/ClusterController.actor.cpp
@@ -2052,8 +2052,17 @@ ACTOR Future<Void> clusterRecruitRemoteFromConfiguration( ClusterControllerData*
 void clusterRegisterMaster( ClusterControllerData* self, RegisterMasterRequest const& req ) {
 	req.reply.send( Void() );
 
-	TraceEvent("MasterRegistrationReceived", self->id).detail("MasterId", req.id).detail("Master", req.mi.toString()).detail("Tlogs", describe(req.logSystemConfig.tLogs)).detail("Resolvers", req.resolvers.size())
-		.detail("RecoveryState", (int)req.recoveryState).detail("RegistrationCount", req.registrationCount).detail("Proxies", req.proxies.size()).detail("RecoveryCount", req.recoveryCount).detail("Stalled", req.recoveryStalled);
+	TraceEvent("MasterRegistrationReceived", self->id)
+	    .detail("MasterId", req.id)
+	    .detail("Master", req.mi.toString())
+	    .detail("Tlogs", describe(req.logSystemConfig.tLogs))
+	    .detail("Resolvers", req.resolvers.size())
+	    .detail("RecoveryState", (int)req.recoveryState)
+	    .detail("RegistrationCount", req.registrationCount)
+	    .detail("Proxies", req.proxies.size())
+	    .detail("RecoveryCount", req.recoveryCount)
+	    .detail("Stalled", req.recoveryStalled)
+	    .detail("OldestBackupEpoch", req.logSystemConfig.oldestBackupEpoch);
 
 	//make sure the request comes from an active database
 	auto db = &self->db;
diff --git a/fdbserver/TagPartitionedLogSystem.actor.cpp b/fdbserver/TagPartitionedLogSystem.actor.cpp
index 146430cbee..9e94c2e5a1 100644
--- a/fdbserver/TagPartitionedLogSystem.actor.cpp
+++ b/fdbserver/TagPartitionedLogSystem.actor.cpp
@@ -202,7 +202,7 @@ struct TagPartitionedLogSystem : ILogSystem, ReferenceCounted<TagPartitionedLogS
 	TagPartitionedLogSystem(UID dbgid, LocalityData locality, LogEpoch e,
 	                        Optional<PromiseStream<Future<Void>>> addActor = Optional<PromiseStream<Future<Void>>>())
 	  : dbgid(dbgid), logSystemType(LogSystemType::empty), expectedLogSets(0), logRouterTags(0), txsTags(0),
-	    repopulateRegionAntiQuorum(0), epoch(e), oldestBackupEpoch(e), recoveryCompleteWrittenToCoreState(false),
+	    repopulateRegionAntiQuorum(0), epoch(e), oldestBackupEpoch(0), recoveryCompleteWrittenToCoreState(false),
 	    locality(locality), remoteLogsWrittenToCoreState(false), hasRemoteServers(false), stopped(false),
 	    addActor(addActor), popActors(false) {}
 
@@ -309,6 +309,7 @@ struct TagPartitionedLogSystem : ILogSystem, ReferenceCounted<TagPartitionedLogS
 		}
 
 		logSystem->logSystemType = lsConf.logSystemType;
+		logSystem->oldestBackupEpoch = lsConf.oldestBackupEpoch;
 		return logSystem;
 	}
 
@@ -1394,6 +1395,7 @@ struct TagPartitionedLogSystem : ILogSystem, ReferenceCounted<TagPartitionedLogS
 			}
 			logset->backupWorkers.push_back(worker);
 		}
+		TraceEvent("SetOldestBackupEpoch", dbgid).detail("Epoch", oldestBackupEpoch);
 		backupWorkerChanged.trigger();
 	}