QmlDesigner: Improve performance of ConnectionManager

This is a pertial cherry-pick from master.
See commit: b9d59edeb16675c3c1442b36c63c156cd8236d04
I removed the changes to the process deletion.
This requires an extra cleanup patch in master.

Change-Id: If845ea44f483c5d3c646595ff9298bcdd3dfd59a
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

4 files changed, 17 insertions, 19 deletions

diff --git a/src/plugins/qmldesigner/designercore/instances/connectionmanager.cpp b/src/plugins/qmldesigner/designercore/instances/connectionmanager.cpp
index 7db7913c56..eb994376ea 100644
--- a/src/plugins/qmldesigner/designercore/instances/connectionmanager.cpp
+++ b/src/plugins/qmldesigner/designercore/instances/connectionmanager.cpp
@@ -53,17 +53,18 @@ void ConnectionManager::setUp(NodeInstanceServerInterface *nodeInstanceServerPro
 {
     BaseConnectionManager::setUp(nodeInstanceServerProxy, qrcMappingString, target, view);
 
-    m_localServer = std::make_unique<QLocalServer>();
-    QString socketToken(QUuid::createUuid().toString());
-    m_localServer->listen(socketToken);
-    m_localServer->setMaxPendingConnections(3);
-
     PuppetCreator puppetCreator(target, view->model());
     puppetCreator.setQrcMappingString(qrcMappingString);
 
     puppetCreator.createQml2PuppetExecutableIfMissing();
 
     for (Connection &connection : m_connections) {
+
+        QString socketToken(QUuid::createUuid().toString());
+        connection.localServer = std::make_unique<QLocalServer>();
+        connection.localServer->listen(socketToken);
+        connection.localServer->setMaxPendingConnections(1);
+
         connection.qmlPuppetProcess = puppetCreator.createPuppetProcess(
             connection.mode,
             socketToken,
@@ -71,10 +72,11 @@ void ConnectionManager::setUp(NodeInstanceServerInterface *nodeInstanceServerPro
             [&](int exitCode, QProcess::ExitStatus exitStatus) {
                 processFinished(exitCode, exitStatus, connection.name);
             });
+    }
 
-        const int second = 1000;
+    const int second = 1000;
+    for (Connection &connection : m_connections) {
         int waitConstant = 8 * second;
-
         if (!connection.qmlPuppetProcess->waitForStarted(waitConstant)) {
             closeSocketsAndKillProcesses();
             showCannotConnectToPuppetWarningAndSwitchToEditMode();
@@ -84,11 +86,11 @@ void ConnectionManager::setUp(NodeInstanceServerInterface *nodeInstanceServerPro
         waitConstant /= 2;
 
         bool connectedToPuppet = true;
-        if (!m_localServer->hasPendingConnections())
-            connectedToPuppet = m_localServer->waitForNewConnection(waitConstant);
+        if (!connection.localServer->hasPendingConnections())
+            connectedToPuppet = connection.localServer->waitForNewConnection(waitConstant);
 
         if (connectedToPuppet) {
-            connection.socket.reset(m_localServer->nextPendingConnection());
+            connection.socket.reset(connection.localServer->nextPendingConnection());
             QObject::connect(connection.socket.get(), &QIODevice::readyRead, this, [&] {
                 readDataStream(connection);
             });
@@ -97,9 +99,8 @@ void ConnectionManager::setUp(NodeInstanceServerInterface *nodeInstanceServerPro
             showCannotConnectToPuppetWarningAndSwitchToEditMode();
             return;
         }
+        connection.localServer->close();
     }
-
-    m_localServer->close();
 }
 
 void ConnectionManager::shutDown()
@@ -107,11 +108,6 @@ void ConnectionManager::shutDown()
     BaseConnectionManager::shutDown();
 
     closeSocketsAndKillProcesses();
-
-    m_localServer.reset();
-
-    for (Connection &connection : m_connections)
-        connection.clear();
 }
 
 void ConnectionManager::writeCommand(const QVariant &command)
diff --git a/src/plugins/qmldesigner/designercore/instances/connectionmanager.h b/src/plugins/qmldesigner/designercore/instances/connectionmanager.h
index 4f25724adb..604f787ede 100644
--- a/src/plugins/qmldesigner/designercore/instances/connectionmanager.h
+++ b/src/plugins/qmldesigner/designercore/instances/connectionmanager.h
@@ -70,8 +70,6 @@ private:
     void closeSocketsAndKillProcesses();
 
 private:
-    std::unique_ptr<QLocalServer> m_localServer;
-
     std::vector<Connection> m_connections;
     quint32 m_writeCommandCounter = 0;
 };
diff --git a/src/plugins/qmldesigner/designercore/instances/connectionmanagerinterface.cpp b/src/plugins/qmldesigner/designercore/instances/connectionmanagerinterface.cpp
index 43ff7f48a2..a0d578aa4d 100644
--- a/src/plugins/qmldesigner/designercore/instances/connectionmanagerinterface.cpp
+++ b/src/plugins/qmldesigner/designercore/instances/connectionmanagerinterface.cpp
@@ -26,6 +26,7 @@
 #include "connectionmanagerinterface.h"
 
 #include <QLocalSocket>
+#include <QLocalServer>
 #include <QTimer>
 
 namespace QmlDesigner {
@@ -45,6 +46,7 @@ void ConnectionManagerInterface::Connection::clear()
 {
     qmlPuppetProcess.reset();
     socket.reset();
+    localServer.reset();
     blockSize = 0;
     lastReadCommandCounter = 0;
     timer.reset();
diff --git a/src/plugins/qmldesigner/designercore/instances/connectionmanagerinterface.h b/src/plugins/qmldesigner/designercore/instances/connectionmanagerinterface.h
index ce4206ca98..1edaf7f730 100644
--- a/src/plugins/qmldesigner/designercore/instances/connectionmanagerinterface.h
+++ b/src/plugins/qmldesigner/designercore/instances/connectionmanagerinterface.h
@@ -30,6 +30,7 @@
 
 QT_BEGIN_NAMESPACE
 class QLocalSocket;
+class QLocalServer;
 QT_END_NAMESPACE
 
 namespace ProjectExplorer {
@@ -59,6 +60,7 @@ public:
         QString mode;
         QProcessUniquePointer qmlPuppetProcess;
         std::unique_ptr<QLocalSocket> socket;
+        std::unique_ptr<QLocalServer> localServer;
         quint32 blockSize = 0;
         quint32 lastReadCommandCounter = 0;
         std::unique_ptr<QTimer> timer;