From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Sun, 7 Apr 2013 19:06:16 +0000 (+0200)
Subject: Stop doing find_stream() every time we send out data; it takes some CPU.
X-Git-Tag: 1.0.0~183
X-Git-Url: https://git.sesse.net/?p=cubemap;a=commitdiff_plain;h=a0ad2d9d955fcb5f0aa3cf4f89999c34e8408124;ds=sidebyside

Stop doing find_stream() every time we send out data; it takes some CPU.
---

diff --git a/server.cpp b/server.cpp
index c8d6889..855e21c 100644
--- a/server.cpp
+++ b/server.cpp
@@ -26,17 +26,19 @@ using namespace std;
 Client::Client(int sock)
 	: sock(sock),
 	  state(Client::READING_REQUEST),
+	  stream(NULL),
 	  header_or_error_bytes_sent(0),
 	  bytes_sent(0)
 {
 	request.reserve(1024);
 }
 	
-Client::Client(const ClientProto &serialized)
+Client::Client(const ClientProto &serialized, Stream *stream)
 	: sock(serialized.sock()),
 	  state(State(serialized.state())),
 	  request(serialized.request()),
 	  stream_id(serialized.stream_id()),
+	  stream(stream),
 	  header_or_error(serialized.header_or_error()),
 	  header_or_error_bytes_sent(serialized.header_or_error_bytes_sent()),
 	  bytes_sent(serialized.bytes_sent())
@@ -211,7 +213,8 @@ void Server::add_client(int sock)
 void Server::add_client_from_serialized(const ClientProto &client)
 {
 	MutexLock lock(&mutex);
-	clients.insert(make_pair(client.sock(), Client(client)));
+	Stream *stream = find_stream(client.stream_id());
+	clients.insert(make_pair(client.sock(), Client(client, stream)));
 
 	// Start listening on data from this socket.
 	epoll_event ev;
@@ -398,20 +401,20 @@ sending_header_or_error_again:
 		// but we'll start sending immediately as we get data.
 		// This is postcondition #3.
 		client->state = Client::SENDING_DATA;
-		client->bytes_sent = find_stream(client->stream_id)->data_size;
+		client->bytes_sent = client->stream->data_size;
 		sleeping_clients.push_back(client);
 		return;
 	}
 	case Client::SENDING_DATA: {
 		// See if there's some data we've lost. Ideally, we should drop to a block boundary,
 		// but resync will be the mux's problem.
-		const Stream &stream = *find_stream(client->stream_id);
-		size_t bytes_to_send = stream.data_size - client->bytes_sent;
+		const Stream *stream = client->stream;
+		size_t bytes_to_send = stream->data_size - client->bytes_sent;
 		if (bytes_to_send > BACKLOG_SIZE) {
 			fprintf(stderr, "WARNING: fd %d lost %lld bytes, maybe too slow connection\n",
 			        client->sock,
 			        (long long int)(bytes_to_send - BACKLOG_SIZE));
-			client->bytes_sent = find_stream(client->stream_id)->data_size - BACKLOG_SIZE;
+			client->bytes_sent = stream->data_size - BACKLOG_SIZE;
 			bytes_to_send = BACKLOG_SIZE;
 		}
 
@@ -421,10 +424,10 @@ sending_header_or_error_again:
 			size_t bytes_first_part = BACKLOG_SIZE - (client->bytes_sent % BACKLOG_SIZE);
 
 			iovec iov[2];
-			iov[0].iov_base = const_cast<char *>(stream.data + (client->bytes_sent % BACKLOG_SIZE));
+			iov[0].iov_base = const_cast<char *>(stream->data + (client->bytes_sent % BACKLOG_SIZE));
 			iov[0].iov_len = bytes_first_part;
 
-			iov[1].iov_base = const_cast<char *>(stream.data);
+			iov[1].iov_base = const_cast<char *>(stream->data);
 			iov[1].iov_len = bytes_to_send - bytes_first_part;
 
 			do {
@@ -433,7 +436,7 @@ sending_header_or_error_again:
 		} else {
 			do {
 				ret = write(client->sock,
-					    stream.data + (client->bytes_sent % BACKLOG_SIZE),
+					    stream->data + (client->bytes_sent % BACKLOG_SIZE),
 					    bytes_to_send);
 			} while (ret == -1 && errno == EINTR);
 		}
@@ -451,7 +454,7 @@ sending_header_or_error_again:
 		}
 		client->bytes_sent += ret;
 
-		if (client->bytes_sent == stream.data_size) {
+		if (client->bytes_sent == stream->data_size) {
 			// We don't have any more data for this client, so put it to sleep.
 			// This is postcondition #3.
 			put_client_to_sleep(client);
@@ -485,6 +488,7 @@ int Server::parse_request(Client *client)
 	}
 
 	client->stream_id = request_tokens[1];
+	client->stream = streams[client->stream_id];
 	client->request.clear();
 
 	return 200;  // OK!
diff --git a/server.h b/server.h
index 24e2fcb..fd309f4 100644
--- a/server.h
+++ b/server.h
@@ -15,6 +15,7 @@
 
 class ClientProto;
 class CubemapStateProto;
+class Stream;
 class StreamProto;
 
 struct Client {
@@ -22,7 +23,7 @@ struct Client {
 	Client(int sock);
 
 	// Serialization/deserialization.
-	Client(const ClientProto &serialized);
+	Client(const ClientProto &serialized, Stream *stream);
 	ClientProto serialize() const;
 
 	// The file descriptor associated with this socket.
@@ -38,6 +39,7 @@ struct Client {
 	// What stream we're connecting to; parsed from <request>.
 	// Not relevant for READING_REQUEST.
 	std::string stream_id;
+	Stream *stream;
 
 	// The header we want to send. This is nominally a copy of Stream::header,
 	// but since that might change on reconnects etc., we keep a local copy here.