[SERVER] Improve handling of byte stats counters

Less writes to variables, more up-to-date values for uplinks.

3 files changed, 29 insertions, 19 deletions

diff --git a/src/server/globals.h b/src/server/globals.h
index 798f4ee..2dbabd5 100644
--- a/src/server/globals.h
+++ b/src/server/globals.h
@@ -68,6 +68,7 @@ struct _dnbd3_connection
 	int nextReplicationIndex;   // Which index in the cache map we should start looking for incomplete blocks at
 	uint64_t replicationHandle; // Handle of pending replication request
 	uint64_t bytesReceived;     // Number of bytes received by the connection.
+	uint64_t lastBytesReceived; // Number of bytes received last time we updated the global counter.
 	int queueLen;               // length of queue
 	dnbd3_queued_request_t queue[SERVER_MAX_UPLINK_QUEUE];
 };
@@ -123,11 +124,11 @@ struct _dnbd3_image
 struct _dnbd3_client
 {
 #define HOSTNAMELEN (48)
-	uint64_t bytesSent;    // Byte counter for this client. Use statsLock when accessing
+	uint64_t bytesSent;     // Byte counter for this client. Use statsLock when accessing.
+	uint64_t lastBytesSent; // Byte counter from when we last added to global counter. Use statsLock when accessing.
 	dnbd3_image_t *image;
-	size_t tmpBytesSent;   // Temporary byte counter that gets added to the global counter periodically. Use statsLock when accessing
 	int sock;
-	bool isServer;         // true if a server in proxy mode, false if real client
+	bool isServer;          // true if a server in proxy mode, false if real client
 	dnbd3_host_t host;
 	char hostName[HOSTNAMELEN];
 	pthread_mutex_t sendMutex;
diff --git a/src/server/net.c b/src/server/net.c
index 09121c3..79d6cfa 100644
--- a/src/server/net.c
+++ b/src/server/net.c
@@ -61,9 +61,9 @@ static bool dnbd3_addClient(dnbd3_client_t *client);
 void net_updateGlobalSentStatsFromClient(dnbd3_client_t * const client)
 {
 	spin_lock( &statisticsSentLock );
-	totalBytesSent += client->tmpBytesSent;
+	totalBytesSent += ( client->bytesSent - client->lastBytesSent );
 	spin_unlock( &statisticsSentLock );
-	client->tmpBytesSent = 0;
+	client->lastBytesSent = client->bytesSent;
 }
 
 static inline bool recv_request_header(int sock, dnbd3_request_t *request)
@@ -197,6 +197,16 @@ void* net_handleNewConnection(void *clientPtr)
 	spin_init( &client->lock, PTHREAD_PROCESS_PRIVATE );
 	spin_init( &client->statsLock, PTHREAD_PROCESS_PRIVATE );
 	pthread_mutex_init( &client->sendMutex, NULL );
+
+	spin_lock( &client->lock );
+	host_to_string( &client->host, client->hostName, HOSTNAMELEN );
+	client->hostName[HOSTNAMELEN-1] = '\0';
+	spin_unlock( &client->lock );
+	spin_lock( &client->statsLock );
+	client->bytesSent = 0;
+	client->lastBytesSent = 0;
+	spin_unlock( &client->statsLock );
+
 	if ( !dnbd3_addClient( client ) ) {
 		dnbd3_freeClient( client );
 		logadd( LOG_WARNING, "Could not add new client to list when connecting" );
@@ -223,11 +233,6 @@ void* net_handleNewConnection(void *clientPtr)
 	memset( &payload, 0, sizeof(payload) );
 	reply.magic = dnbd3_packet_magic;
 
-	spin_lock( &client->lock );
-	host_to_string( &client->host, client->hostName, HOSTNAMELEN );
-	client->hostName[HOSTNAMELEN-1] = '\0';
-	spin_unlock( &client->lock );
-
 	// Receive first packet's payload
 	if ( recv_request_payload( client->sock, request.size, &payload ) ) {
 		char *image_name;
@@ -461,11 +466,6 @@ void* net_handleNewConnection(void *clientPtr)
 				spin_lock( &client->statsLock );
 				// Global per-client counter
 				client->bytesSent += request.size; // Increase counter for statistics.
-				// Local counter that gets added to the global total bytes sent counter periodically
-				client->tmpBytesSent += request.size;
-				if ( client->tmpBytesSent > 100000000 ) {
-					net_updateGlobalSentStatsFromClient( client );
-				}
 				spin_unlock( &client->statsLock );
 				break;
 
diff --git a/src/server/uplink.c b/src/server/uplink.c
index e899ed9..2f71a4c 100644
--- a/src/server/uplink.c
+++ b/src/server/uplink.c
@@ -23,6 +23,7 @@ static void uplink_handleReceive(dnbd3_connection_t *link);
 static int uplink_sendKeepalive(const int fd);
 static void uplink_addCrc32(dnbd3_connection_t *uplink);
 static void uplink_sendReplicationRequest(dnbd3_connection_t *link);
+static void uplink_updateGlobalReceivedCounter(dnbd3_connection_t *link);
 
 // ############ uplink connection handling
 
@@ -64,6 +65,7 @@ bool uplink_init(dnbd3_image_t *image, int sock, dnbd3_host_t *host, int version
 	spin_init( &link->rttLock, PTHREAD_PROCESS_PRIVATE );
 	link->image = image;
 	link->bytesReceived = 0;
+	link->lastBytesReceived = 0;
 	link->queueLen = 0;
 	link->fd = -1;
 	link->signal = NULL;
@@ -378,6 +380,7 @@ static void* uplink_mainloop(void *data)
 				link->fd = -1;
 				close( fd );
 			}
+			uplink_updateGlobalReceivedCounter( link );
 		}
 		// See if we should trigger an RTT measurement
 		spin_lock( &link->rttLock );
@@ -457,9 +460,7 @@ static void* uplink_mainloop(void *data)
 	spin_destroy( &link->rttLock );
 	free( link->recvBuffer );
 	link->recvBuffer = NULL;
-	spin_lock( &statisticsReceivedLock );
-	totalBytesReceived += link->bytesReceived;
-	spin_unlock( &statisticsReceivedLock );
+	uplink_updateGlobalReceivedCounter( link );
 	free( link );
 	return NULL ;
 }
@@ -648,7 +649,6 @@ static void uplink_handleReceive(dnbd3_connection_t *link)
 				pthread_mutex_unlock( &client->sendMutex );
 				if ( bytesSent != 0 ) {
 					client->bytesSent += bytesSent;
-					client->tmpBytesSent += bytesSent;
 				}
 				spin_unlock( &client->statsLock );
 				spin_lock( &link->queueLock );
@@ -722,3 +722,12 @@ static void uplink_addCrc32(dnbd3_connection_t *uplink)
 		close( fd );
 	}
 }
+
+static void uplink_updateGlobalReceivedCounter(dnbd3_connection_t *link)
+{
+	spin_lock( &statisticsReceivedLock );
+	totalBytesReceived += ( link->bytesReceived - link->lastBytesReceived );
+	link->lastBytesReceived = 0;
+	spin_unlock( &statisticsReceivedLock );
+}
+