Sample actors waiting on network

fdbclient/InstrumentRequest.h

@@ -0,0 +1,50 @@
+/*
+ * InstrumentRequest.h
+ *
+ * This source file is part of the FoundationDB open source project
+ *
+ * Copyright 2013-2021 Apple Inc. and the FoundationDB project authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "flow/flow.h"
+#include "flow/network.h"
+
+// Used to manually instrument waiting actors to collect samples for the
+// sampling profiler.
+struct InstrumentRequest {
+	unsigned index;
+
+	InstrumentRequest() {}
+
+	// This API isn't great. Ideally, no cleanup call is needed. I ran into an
+	// issue around the destructor being called twice because an instance of
+	// this class has to be stored as a class member (otherwise it goes away
+	// when wait is called), and due to how Flow does code generation the
+	// member will be default initialized and then initialized again when it is
+	// initially set. Then, the destructor will be called twice, causing issues
+	// when the WriteOnlySet tries to erase the same index twice. I'm working
+	// on this :)
+
+	void start() {
+		index = g_network->getActorLineageSet().insert(currentLineage);
+	}
+	
+	void complete() {
+		g_network->getActorLineageSet().erase(index);
+	}
+};
+

fdbclient/NativeAPI.actor.cpp

@@ -36,6 +36,7 @@
 #include "fdbclient/ClusterInterface.h"
 #include "fdbclient/CoordinationInterface.h"
 #include "fdbclient/DatabaseContext.h"
+#include "fdbclient/InstrumentRequest.h"
 #include "fdbclient/JsonBuilder.h"
 #include "fdbclient/KeyRangeMap.h"
 #include "fdbclient/Knobs.h"
@@ -1770,6 +1771,7 @@ void runNetwork() {
 	if (networkOptions.traceDirectory.present() && networkOptions.runLoopProfilingEnabled) {
 		setupRunLoopProfiler();
 	}
+	setupSamplingProfiler();
 
 	g_network->run();
 
@@ -3025,6 +3027,8 @@ ACTOR Future<Standalone<RangeResultRef>> getRange(Database cx,
 						throw deterministicRandom()->randomChoice(
 						    std::vector<Error>{ transaction_too_old(), future_version() });
 					}
+					state InstrumentRequest request;
+					request.start();
 					GetKeyValuesReply _rep =
 					    wait(loadBalance(cx.getPtr(),
 					                     beginServer.second,
@@ -3035,6 +3039,7 @@ ACTOR Future<Standalone<RangeResultRef>> getRange(Database cx,
 					                     cx->enableLocalityLoadBalance ? &cx->queueModel : nullptr));
 					rep = _rep;
 					++cx->transactionPhysicalReadsCompleted;
+					request.complete();
 				} catch (Error&) {
 					++cx->transactionPhysicalReadsCompleted;
 					throw;

fdbrpc/FlowTests.actor.cpp

@@ -24,6 +24,7 @@
 #include "flow/UnitTest.h"
 #include "flow/DeterministicRandom.h"
 #include "flow/IThreadPool.h"
+#include "flow/WriteOnlySet.h"
 #include "fdbrpc/fdbrpc.h"
 #include "fdbrpc/IAsyncFile.h"
 #include "flow/TLSConfig.actor.h"
@@ -283,6 +284,9 @@ struct YieldMockNetwork final : INetwork, ReferenceCounted<YieldMockNetwork> {
 		static TLSConfig emptyConfig;
 		return emptyConfig;
 	}
+	ActorLineageSet& getActorLineageSet() override {
+		throw std::exception();
+	}
 	ProtocolVersion protocolVersion() override { return baseNetwork->protocolVersion(); }
 };
 

fdbrpc/sim2.actor.cpp

@@ -31,6 +31,7 @@
 #include "flow/IThreadPool.h"
 #include "flow/ProtocolVersion.h"
 #include "flow/Util.h"
+#include "flow/WriteOnlySet.h"
 #include "fdbrpc/IAsyncFile.h"
 #include "fdbrpc/AsyncFileCached.actor.h"
 #include "fdbrpc/AsyncFileNonDurable.actor.h"
@@ -975,6 +976,10 @@ public:
 
 	bool checkRunnable() override { return net2->checkRunnable(); }
 
+	ActorLineageSet& getActorLineageSet() override {
+		return actorLineageSet;
+	}
+
 	void stop() override { isStopped = true; }
 	void addStopCallback(std::function<void()> fn) override { stopCallbacks.emplace_back(std::move(fn)); }
 	bool isSimulated() const override { return true; }
@@ -2117,6 +2122,8 @@ public:
 	// Whether or not yield has returned true during the current iteration of the run loop
 	bool yielded;
 	int yield_limit; // how many more times yield may return false before next returning true
+
+	ActorLineageSet actorLineageSet;
 };
 
 class UDPSimSocket : public IUDPSocket, ReferenceCounted<UDPSimSocket> {

flow/Net2.actor.cpp

@@ -198,6 +198,8 @@ public:
 
 	bool checkRunnable() override;
 
+	ActorLineageSet& getActorLineageSet() override;
+
 	bool useThreadPool;
 
 	// private:
@@ -225,6 +227,8 @@ public:
 	std::atomic<bool> stopped;
 	mutable std::map<IPAddress, bool> addressOnHostCache;
 
+	ActorLineageSet actorLineageSet;
+
 	std::atomic<bool> started;
 
 	uint64_t numYields;
@@ -1377,6 +1381,10 @@ bool Net2::checkRunnable() {
 	return !started.exchange(true);
 }
 
+ActorLineageSet& Net2::getActorLineageSet() {
+	return actorLineageSet;
+}
+
 void Net2::run() {
 	TraceEvent::setNetworkThread();
 	TraceEvent("Net2Running");

flow/Platform.actor.cpp

@@ -3679,8 +3679,7 @@ void* sampleThread(void* arg) {
 	while (true) {
 		threadSleep(1.0); // TODO: Read sample rate from global config
 
-		// TODO: Copy actor lineage of currently running actor
-		// Read currentLineage
+		// Get actor lineage of currently running actor.
 		auto actorLineage = currentLineageThreadSafe.get();
 		printf("Currently running actor lineage (%p):\n", actorLineage.getPtr());
 		auto stack = actorLineage->stack(&StackLineage::actorName);
@@ -3690,11 +3689,16 @@ void* sampleThread(void* arg) {
 		}
 		printf("\n");
 
+		// Get lineage of actors waiting on disk.
 		auto diskAlps = IAsyncFileSystem::filesystem()->getActorLineageSet().copy();
-		printf("Disk ALPs: %d\n", diskAlps.size());
+		// printf("Disk ALPs: %d\n", diskAlps.size());
+
+		// TODO: Get lineage of actors waiting on network
+		auto networkAlps = g_network->getActorLineageSet().copy();
+		printf("Network ALPs: %d\n", networkAlps.size());
 
 		// TODO: Call collect on all actor lineages
-		for (auto actorLineage : diskAlps) {
+		for (auto actorLineage : networkAlps) {
 			auto stack = actorLineage->stack(&StackLineage::actorName);
 			while (!stack.empty()) {
 				printf("%s ", stack.top());

flow/network.h

@@ -34,6 +34,7 @@
 #include "flow/Arena.h"
 #include "flow/IRandom.h"
 #include "flow/Trace.h"
+#include "flow/WriteOnlySet.h"
 
 enum class TaskPriority {
 	Max = 1000000,
@@ -535,6 +536,9 @@ public:
 	// returns false.
 	virtual bool checkRunnable() = 0;
 
+	// Returns the shared memory data structure used to store actor lineages.
+	virtual ActorLineageSet& getActorLineageSet() = 0;
+
 	virtual ProtocolVersion protocolVersion() = 0;
 
 	// Shorthand for transport().getLocalAddress()