Add hash to StringRef. Use unordered maps for storing tags. Create some helpful typedefs.

fdbclient/DatabaseContext.h

@@ -167,7 +167,7 @@ public:
 	UID dbId;
 	bool internal; // Only contexts created through the C client and fdbcli are non-internal
 
-	std::map<TagThrottleInfo::Priority, std::map<Standalone<StringRef>, TagThrottleInfo>> throttledTags;
+	PrioritizedTagThrottleMap throttledTags;
 
 	CounterCollection cc;
 

fdbclient/MasterProxyInterface.h

@@ -165,7 +165,7 @@ struct GetReadVersionReply {
 	bool locked;
 	Optional<Value> metadataVersion;
 
-	std::map<Standalone<StringRef>, TagThrottleInfo> tagThrottleInfo;
+	TagThrottleMap tagThrottleInfo;
 
 	GetReadVersionReply() : version(invalidVersion), locked(false) {}
 

fdbclient/TagThrottle.h

@@ -86,6 +86,8 @@ struct TagThrottleInfo {
 	}
 };
 
+BINARY_SERIALIZABLE(TagThrottleInfo::Priority);
+
 class TagSet {
 public:
 	typedef std::set<StringRef>::const_iterator const_iterator;
@@ -148,7 +150,8 @@ struct dynamic_size_traits<TagSet> : std::true_type {
 	}
 };
 
-BINARY_SERIALIZABLE(TagThrottleInfo::Priority);
+typedef std::unordered_map<Standalone<StringRef>, TagThrottleInfo, std::hash<StringRef>> TagThrottleMap;
+typedef std::map<TagThrottleInfo::Priority, TagThrottleMap> PrioritizedTagThrottleMap;
 
 namespace ThrottleApi {
 	// Currently, only 1 tag in a key is supported

fdbserver/MasterProxyServer.actor.cpp

@@ -99,7 +99,7 @@ struct ProxyStats {
 
 ACTOR Future<Void> getRate(UID myID, Reference<AsyncVar<ServerDBInfo>> db, int64_t* inTransactionCount, int64_t* inBatchTransactionCount, double* outTransactionRate,
 						   double* outBatchTransactionRate, GetHealthMetricsReply* healthMetricsReply, GetHealthMetricsReply* detailedHealthMetricsReply,
-						   std::map<TagThrottleInfo::Priority, std::map<Standalone<StringRef>, TagThrottleInfo>> *throttledTags) {
+						   PrioritizedTagThrottleMap *throttledTags) {
 	state Future<Void> nextRequestTimer = Never();
 	state Future<Void> leaseTimeout = Never();
 	state Future<GetRateInfoReply> reply = Never();
@@ -1292,7 +1292,7 @@ ACTOR Future<GetReadVersionReply> getLiveCommittedVersion(ProxyCommitData* commi
 }
 
 ACTOR Future<Void> sendGrvReplies(Future<GetReadVersionReply> replyFuture, std::vector<GetReadVersionRequest> requests,
-                                  ProxyStats* stats, Version minKnownCommittedVersion, std::map<TagThrottleInfo::Priority, std::map<Standalone<StringRef>, TagThrottleInfo>> throttledTags) {
+                                  ProxyStats* stats, Version minKnownCommittedVersion, PrioritizedTagThrottleMap throttledTags) {
 	GetReadVersionReply _baseReply = wait(replyFuture);
 	GetReadVersionReply baseReply = _baseReply;
 	double end = g_network->timer();
@@ -1353,7 +1353,7 @@ ACTOR static Future<Void> transactionStarter(
 	state Deque<GetReadVersionRequest> batchQueue;
 	state vector<MasterProxyInterface> otherProxies;
 
-	state std::map<TagThrottleInfo::Priority, std::map<Standalone<StringRef>, TagThrottleInfo>> throttledTags;
+	state PrioritizedTagThrottleMap throttledTags;
 
 	state PromiseStream<double> replyTimes;
 	addActor.send(getRate(proxy.id(), db, &transactionCount, &batchTransactionCount, &normalRateInfo.rate, &batchRateInfo.rate, healthMetricsReply, detailedHealthMetricsReply, &throttledTags));

fdbserver/Ratekeeper.actor.cpp

@@ -187,8 +187,7 @@ struct RatekeeperData {
 	double lastWarning;
 	double lastSSListFetchedTimestamp;
 
-	typedef std::map<Standalone<StringRef>, TagThrottleInfo> ThrottleMap;
+	PrioritizedTagThrottleMap tagThrottles;
-	std::map<TagThrottleInfo::Priority, ThrottleMap> tagThrottles;
 
 	RatekeeperLimits normalLimits;
 	RatekeeperLimits batchLimits;
@@ -417,8 +416,8 @@ ACTOR Future<Void> monitorThrottlingChanges(RatekeeperData *self) {
 				}
 
 				TraceEvent("RatekeeperReadThrottles").detail("NumThrottledTags", throttledTags.get().size());
-				std::map<TagThrottleInfo::Priority, RatekeeperData::ThrottleMap> newThrottles;
+				PrioritizedTagThrottleMap newThrottles;
-				std::map<TagThrottleInfo::Priority, std::pair<RatekeeperData::ThrottleMap::iterator, RatekeeperData::ThrottleMap::iterator>> oldThrottleIterators;
+				std::map<TagThrottleInfo::Priority, std::pair<TagThrottleMap::iterator, TagThrottleMap::iterator>> oldThrottleIterators;
 				for(auto t : self->tagThrottles) {
 					oldThrottleIterators[t.first] = std::make_pair(t.second.begin(), t.second.end());
 				}
@@ -473,7 +472,7 @@ ACTOR Future<Void> monitorThrottlingChanges(RatekeeperData *self) {
 	}
 }
 
-void updateRate(RatekeeperData* self, RatekeeperLimits* limits, RatekeeperData::ThrottleMap& throttledTags) {
+void updateRate(RatekeeperData* self, RatekeeperLimits* limits, TagThrottleMap& throttledTags) {
 	//double controlFactor = ;  // dt / eFoldingTime
 
 	double actualTps = self->smoothReleasedTransactions.smoothRate();

fdbserver/RatekeeperInterface.h

@@ -59,7 +59,7 @@ struct GetRateInfoReply {
 	double leaseDuration;
 	HealthMetrics healthMetrics;
 
-	std::map<TagThrottleInfo::Priority, std::map<Standalone<StringRef>, TagThrottleInfo>> throttledTags;
+	PrioritizedTagThrottleMap throttledTags;
 
 	template <class Ar>
 	void serialize(Ar& ar) {

fdbserver/storageserver.actor.cpp

@@ -460,7 +460,7 @@ public:
 			  : tag(tag), count(count), fractionalBusyness((double)count/totalCount), elapsed(elapsed) {}
 		};
 
-		std::map<Standalone<StringRef>, int64_t> intervalCounts; // TODO: use a hash for performance
+		std::unordered_map<Standalone<StringRef>, int64_t, std::hash<StringRef>> intervalCounts;
 		int64_t intervalTotalCount = 0;
 		Standalone<StringRef> busiestTag;
 		int64_t busiestTagCount = 0;

flow/Arena.h

@@ -585,7 +585,17 @@ private:
 };
 #pragma pack( pop )
 
-template<>
+namespace std {
+	template <>
+	struct hash<StringRef> {
+		static constexpr std::hash<std::string_view> hashFunc{};
+		std::size_t operator()(StringRef const& tag) const {
+			return hashFunc(std::string_view((const char*)tag.begin(), tag.size()));
+		}
+	};
+}
+
+template <>
 struct TraceableString<StringRef> {
 	static const char* begin(StringRef value) {
 		return reinterpret_cast<const char*>(value.begin());

flow/flat_buffers.h

@@ -174,6 +174,29 @@ struct vector_like_traits<std::map<Key, T, Compare, Allocator>> : std::true_type
 		return v.begin();
 	}
 };
+template <class Key, class T, class Hash, class Pred, class Allocator>
+struct vector_like_traits<std::unordered_map<Key, T, Hash, Pred, Allocator>> : std::true_type {
+	using Vec = std::unordered_map<Key, T, Hash, Pred, Allocator>;
+	using value_type = std::pair<Key, T>;
+	using iterator = typename Vec::const_iterator;
+	using insert_iterator = std::insert_iterator<Vec>;
+
+	template <class Context>
+	static size_t num_entries(const Vec& v, Context&) {
+		return v.size();
+	}
+	template <class Context>
+	static void reserve(Vec& v, size_t size, Context&) {}
+
+	template <class Context>
+	static insert_iterator insert(Vec& v, Context&) {
+		return std::inserter(v, v.end());
+	}
+	template <class Context>
+	static iterator begin(const Vec& v, Context&) {
+		return v.begin();
+	}
+};
 
 template <class Key, class Compare, class Allocator>
 struct vector_like_traits<std::set<Key, Compare, Allocator>> : std::true_type {