From a0a4207ce2210d350d2c7bf152ba00859c78f013 Mon Sep 17 00:00:00 2001
From: sfc-gh-tclinkenbeard <trevor.clinkenbeard@snowflake.com>
Date: Wed, 11 Aug 2021 23:41:19 -0700
Subject: [PATCH] Capture deep copy of machine_info in printSnapshotTeamsInfo

---
 fdbserver/DataDistribution.actor.cpp | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/fdbserver/DataDistribution.actor.cpp b/fdbserver/DataDistribution.actor.cpp
index ef925b1f19..40a089e4d0 100644
--- a/fdbserver/DataDistribution.actor.cpp
+++ b/fdbserver/DataDistribution.actor.cpp
@@ -108,12 +108,24 @@ struct TCServerInfo : public ReferenceCounted<TCServerInfo> {
 	~TCServerInfo();
 };
 
-struct TCMachineInfo : public ReferenceCounted<TCMachineInfo> {
+class TCMachineInfo : public ReferenceCounted<TCMachineInfo> {
+	TCMachineInfo() = default;
+
+public:
 	std::vector<Reference<TCServerInfo>> serversOnMachine; // SOMEDAY: change from vector to set
 	Standalone<StringRef> machineID;
 	std::vector<Reference<TCMachineTeamInfo>> machineTeams; // SOMEDAY: split good and bad machine teams.
 	LocalityEntry localityEntry;
 
+	Reference<TCMachineInfo> clone() const {
+		auto result = Reference<TCMachineInfo>(new TCMachineInfo);
+		result->serversOnMachine = serversOnMachine;
+		result->machineID = machineID;
+		result->machineTeams = machineTeams;
+		result->localityEntry = localityEntry;
+		return result;
+	}
+
 	explicit TCMachineInfo(Reference<TCServerInfo> server, const LocalityEntry& entry) : localityEntry(entry) {
 		ASSERT(serversOnMachine.empty());
 		serversOnMachine.push_back(server);
@@ -3011,7 +3023,10 @@ ACTOR Future<Void> printSnapshotTeamsInfo(Reference<DDTeamCollection> self) {
 			configuration = self->configuration;
 			server_info = self->server_info;
 			teams = self->teams;
-			machine_info = self->machine_info;
+			// Perform deep copy so we have a consistent snapshot, even if yields are performed
+			for (const auto& [machineId, info] : self->machine_info) {
+				machine_info.emplace(machineId, info->clone());
+			}
 			machineTeams = self->machineTeams;
 			// internedLocalityRecordKeyNameStrings = self->machineLocalityMap._keymap->_lookuparray;
 			// machineLocalityMapEntryArraySize = self->machineLocalityMap.size();