Name the RocksDB background threads

fdbserver/CoroFlow.actor.cpp

@@ -58,8 +58,7 @@ struct Coroutine /*: IThreadlike*/ {
 
 	void start() {
 		int result = Coro_startCoro_( swapCoro(coro), coro, this, &entry );
-		if (result == ENOMEM) 
-			platform::outOfMemory();
+		if (result == ENOMEM) platform::outOfMemory();
 	}
 
 	void unblock() {
@@ -136,7 +135,7 @@ class WorkPool : public IThreadPool, public ReferenceCounted<WorkPool<Threadlike
 			try {
 				if(!stop)
 					userData->init();
-				
+
 				while (!stop) {
 					pool->queueLock.enter();
 					if (pool->work.empty()) {
@@ -178,8 +177,8 @@ class WorkPool : public IThreadPool, public ReferenceCounted<WorkPool<Threadlike
 	Error error;
 
 	ACTOR Future<Void> stopOnError( WorkPool* w ) {
-		try { 
-			wait( w->getError() );  
+		try {
+			wait(w->getError());
 			ASSERT(false);
 		} catch (Error& e) {
 			w->stop(e);
@@ -200,7 +199,7 @@ public:
 	}
 
 	virtual Future<Void> getError() { return pool->anyError.getResult(); }
-	virtual void addThread( IThreadPoolReceiver* userData ) {
+	virtual void addThread(IThreadPoolReceiver* userData, const char*) {
 		checkError();
 
 		auto w = new Worker(pool.getPtr(), userData);
@@ -245,7 +244,7 @@ public:
 		for(int i=0; i<pool->workers.size(); i++)
 			pool->workers[i]->stop = true;
 
-		std::vector<Worker*> idle; 
+		std::vector<Worker*> idle;
 		std::swap(idle, pool->idle);
 		pool->queueLock.leave();
 
@@ -294,8 +293,7 @@ void CoroThreadPool::init()
 {
 	if (!current_coro) {
 		current_coro = main_coro = Coro_new();
-		if (main_coro == NULL) 
-			platform::outOfMemory();
+		if (main_coro == NULL) platform::outOfMemory();
 
 		Coro_initializeMainCoro(main_coro);
 		//printf("Main thread: %d bytes stack presumed available\n", Coro_bytesLeftOnStack(current_coro));

fdbserver/KeyValueStoreRocksDB.actor.cpp

@@ -359,9 +359,9 @@ struct RocksDBKeyValueStore : IKeyValueStore {
 	{
 		writeThread = createGenericThreadPool();
 		readThreads = createGenericThreadPool();
-		writeThread->addThread(new Writer(db, id));
+		writeThread->addThread(new Writer(db, id), "fdb-rocksdb-wr");
 		for (unsigned i = 0; i < SERVER_KNOBS->ROCKSDB_READ_PARALLELISM; ++i) {
-			readThreads->addThread(new Reader(db));
+			readThreads->addThread(new Reader(db), "fdb-rocksdb-re");
 		}
 	}
 

flow/IThreadPool.cpp

@@ -95,9 +95,9 @@ public:
 	virtual Future<Void> getError() { return Never(); }  // FIXME
 	virtual void addref() { ReferenceCounted<ThreadPool>::addref(); }
 	virtual void delref() { if (ReferenceCounted<ThreadPool>::delref_no_destroy()) stop(); }
-	void addThread( IThreadPoolReceiver* userData ) {
+	void addThread(IThreadPoolReceiver* userData, const char* name) {
 		threads.push_back(new Thread(this, userData));
-		startThread(start, threads.back(), stackSize);
+		startThread(start, threads.back(), stackSize, name);
 	}
 	void post( PThreadAction action ) {
 		ios.post( ActionWrapper( action ) );

flow/IThreadPool.h

@@ -22,6 +22,8 @@
 #define FLOW_ITHREADPOOL_H
 #pragma once
 
+#include <string_view>
+
 #include "flow/flow.h"
 
 // The IThreadPool interface represents a thread pool suitable for doing blocking disk-intensive work
@@ -47,7 +49,7 @@ public:
 	virtual void init() = 0;
 };
 
-struct ThreadAction { 
+struct ThreadAction {
 	virtual void operator()(IThreadPoolReceiver*) = 0;		// self-destructs
 	virtual void cancel() = 0;
 	virtual double getTimeEstimate() = 0;                   // for simulation
@@ -58,7 +60,7 @@ class IThreadPool {
 public:
 	virtual ~IThreadPool() {}
 	virtual Future<Void> getError() = 0;  // asynchronously throws an error if there is an internal error
-	virtual void addThread( IThreadPoolReceiver* userData ) = 0;
+	virtual void addThread(IThreadPoolReceiver* userData, const char* name = nullptr) = 0;
 	virtual void post( PThreadAction action ) = 0;
 	virtual Future<Void> stop(Error const& e = success()) = 0;
 	virtual bool isCoro() const { return false; }

flow/Platform.cpp

@@ -1047,9 +1047,8 @@ void getDiskStatistics(std::string const& directory, uint64_t& currentIOs, uint6
 		reads = total_transfers_read;
 		writes = total_transfers_write;
 		writeSectors = total_blocks_read;
-		readSectors = total_blocks_write;        
+		readSectors = total_blocks_write;
 	}
-	
 }
 
 dev_t getDeviceId(std::string path) {
@@ -2519,11 +2518,19 @@ void setCloseOnExec( int fd ) {
 } // namespace platform
 
 #ifdef _WIN32
-THREAD_HANDLE startThread(void (*func) (void *), void *arg, int stackSize) {
-	return (void *)_beginthread(func, stackSize, arg);
+THREAD_HANDLE startThread(void (*func)(void*), void* arg, int stackSize, const char* name) {
+	// Convert `const char*` to `const wchar*` because Windows.
+	size_t newsize = strlen(orig) + 1;
+	wchar_t* wcstring = new wchar_t[newsize];
+	size_t convertedChars = 0;
+	mbstowcs_s(&convertedChars, wcstring, newsize, name, _TRUNCATE);
+	auto handle = _beginthread(func, stackSize, arg);
+	SetThreadDescription(handle, wcstring);
+	delete[] wcstring;
+	return (void*)handle;
 }
 #elif (defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__))
-THREAD_HANDLE startThread(void *(*func) (void *), void *arg, int stackSize) {
+THREAD_HANDLE startThread(void* (*func)(void*), void* arg, int stackSize, const char* name) {
 	pthread_t t;
 	pthread_attr_t attr;
 
@@ -2542,6 +2549,11 @@ THREAD_HANDLE startThread(void *(*func) (void *), void *arg, int stackSize) {
 	pthread_create(&t, &attr, func, arg);
 	pthread_attr_destroy(&attr);
 
+	if (name != nullptr) {
+		// TODO: Should this just truncate?
+		ASSERT_EQ(pthread_setname_np(t, name), 0);
+	}
+
 	return t;
 }
 #else
@@ -3273,7 +3285,7 @@ int64_t getNumProfilesCaptured() {
 
 void profileHandler(int sig) {
 #ifdef __linux__
-	if(!profileThread) { 
+	if (!profileThread) {
 		return;
 	}
 
@@ -3311,7 +3323,7 @@ void profileHandler(int sig) {
 #endif
 }
 
-void setProfilingEnabled(int enabled) { 
+void setProfilingEnabled(int enabled) {
 #ifdef __linux__
 	if(profileThread && enabled && !profilingEnabled && profileRequested) {
 		profilingEnabled = true;
@@ -3323,7 +3335,7 @@ void setProfilingEnabled(int enabled) {
 	}
 #else
 	// No profiling for other platforms!
-#endif	
+#endif
 }
 
 void* checkThread(void *arg) {

flow/Platform.h

@@ -153,13 +153,13 @@ inline static T& makeDependent(T& value) { return value; }
 #define THREAD_FUNC static void __cdecl
 #define THREAD_FUNC_RETURN void
 #define THREAD_HANDLE void *
-THREAD_HANDLE startThread(void (func) (void *), void *arg, int stackSize = 0);
+THREAD_HANDLE startThread(void(func)(void*), void* arg, int stackSize = 0, const char* name = nullptr);
 #define THREAD_RETURN return
 #elif defined(__unixish__)
 #define THREAD_FUNC static void *
 #define THREAD_FUNC_RETURN void *
 #define THREAD_HANDLE pthread_t
-THREAD_HANDLE startThread(void *(func) (void *), void *arg, int stackSize = 0);
+THREAD_HANDLE startThread(void*(func)(void*), void* arg, int stackSize = 0, const char* name = nullptr);
 #define THREAD_RETURN return NULL
 #else
 #error How do I start a new thread on this platform?

flow/Trace.cpp

@@ -61,7 +61,7 @@ public:
 	Future<Void> getError() {
 		return errors.getFuture();
 	}
-	void addThread( IThreadPoolReceiver* userData ) {
+	void addThread(IThreadPoolReceiver* userData, const char*) {
 		ASSERT( !thread );
 		thread = userData;
 	}