diff --git a/src/libs/utils/launcherpackets.cpp b/src/libs/utils/launcherpackets.cpp
index c81f3532bed..e14705509de 100644
--- a/src/libs/utils/launcherpackets.cpp
+++ b/src/libs/utils/launcherpackets.cpp
@@ -59,13 +59,13 @@ StartProcessPacket::StartProcessPacket(quintptr token)
 void StartProcessPacket::doSerialize(QDataStream &stream) const
 {
     stream << command << arguments << workingDir << env << processMode << writeData << channelMode
-           << standardInputFile;
+           << standardInputFile << belowNormalPriority;
 }
 
 void StartProcessPacket::doDeserialize(QDataStream &stream)
 {
     stream >> command >> arguments >> workingDir >> env >> processMode >> writeData >> channelMode
-           >> standardInputFile;
+           >> standardInputFile >> belowNormalPriority;
 }
 
 
diff --git a/src/libs/utils/launcherpackets.h b/src/libs/utils/launcherpackets.h
index e7c25d51026..9a70da350d6 100644
--- a/src/libs/utils/launcherpackets.h
+++ b/src/libs/utils/launcherpackets.h
@@ -115,6 +115,7 @@ public:
     QByteArray writeData;
     QProcess::ProcessChannelMode channelMode = QProcess::SeparateChannels;
     QString standardInputFile;
+    bool belowNormalPriority = false;
 
 private:
     void doSerialize(QDataStream &stream) const override;
diff --git a/src/libs/utils/launchersocket.cpp b/src/libs/utils/launchersocket.cpp
index e24a4714e58..4a319d1ee8e 100644
--- a/src/libs/utils/launchersocket.cpp
+++ b/src/libs/utils/launchersocket.cpp
@@ -409,6 +409,7 @@ void LauncherHandle::doStart()
     p.writeData = m_writeData;
     p.channelMode = m_channelMode;
     p.standardInputFile = m_standardInputFile;
+    p.belowNormalPriority = m_belowNormalPriority;
     sendPacket(p);
 }
 
diff --git a/src/libs/utils/launchersocket.h b/src/libs/utils/launchersocket.h
index e82a366b165..28f7b5a35b7 100644
--- a/src/libs/utils/launchersocket.h
+++ b/src/libs/utils/launchersocket.h
@@ -102,6 +102,9 @@ public:
     { QMutexLocker locker(&m_mutex); m_environment = environment; }
     void setWorkingDirectory(const QString &dir) { QMutexLocker locker(&m_mutex); m_workingDirectory = dir; }
     QProcess::ExitStatus exitStatus() const { QMutexLocker locker(&m_mutex); return m_exitStatus; }
+
+    void setBelowNormalPriority() { m_belowNormalPriority = true; }
+
 signals:
     void errorOccurred(QProcess::ProcessError error);
     void started();
@@ -181,6 +184,8 @@ private:
 
     CallerHandle *m_callerHandle = nullptr;
 
+    bool m_belowNormalPriority = false;
+
     friend class LauncherSocket;
     friend class CallerHandle;
 };
diff --git a/src/libs/utils/processutils.cpp b/src/libs/utils/processutils.cpp
index 627eb7d36eb..853c4767891 100644
--- a/src/libs/utils/processutils.cpp
+++ b/src/libs/utils/processutils.cpp
@@ -26,6 +26,13 @@
 #include "processutils.h"
 #include <QProcess>
 
+#ifdef Q_OS_WIN
+#ifdef QTCREATOR_PCH_H
+#define CALLBACK WINAPI
+#endif
+#include <qt_windows.h>
+#endif
+
 namespace Utils {
 
 QIODevice::OpenMode ProcessStartHandler::openMode() const
@@ -55,4 +62,16 @@ void ProcessStartHandler::handleProcessStarted(QProcess *process)
     }
 }
 
+
+void ProcessStartHandler::setBelowNormalPriority(QProcess *process)
+{
+#ifdef Q_OS_WIN
+    process->setCreateProcessArgumentsModifier(
+        [](QProcess::CreateProcessArguments *args) {
+            args->flags |= BELOW_NORMAL_PRIORITY_CLASS;
+    });
+#endif // Q_OS_WIN
+}
+
+
 } // namespace Utils
diff --git a/src/libs/utils/processutils.h b/src/libs/utils/processutils.h
index 85c3812be88..9ffef7eca94 100644
--- a/src/libs/utils/processutils.h
+++ b/src/libs/utils/processutils.h
@@ -46,6 +46,7 @@ public:
     QIODevice::OpenMode openMode() const;
     void handleProcessStart(QProcess *process);
     void handleProcessStarted(QProcess *process);
+    void setBelowNormalPriority(QProcess *process);
 
 private:
     ProcessMode m_processMode = ProcessMode::Reader;
diff --git a/src/libs/utils/qtcprocess.cpp b/src/libs/utils/qtcprocess.cpp
index 9c7b12d67fd..390e8e83872 100644
--- a/src/libs/utils/qtcprocess.cpp
+++ b/src/libs/utils/qtcprocess.cpp
@@ -136,8 +136,10 @@ public:
     virtual bool lowPriority() const = 0;
     virtual void setDisableUnixTerminal() = 0;
 
+    void setBelowNormalPriority() { m_belowNormalPriority = true; }
+    bool isBelowNormalPriority() const { return m_belowNormalPriority; }
+
 #ifdef Q_OS_WIN
-    virtual void setCreateProcessArgumentsModifier(QProcess::CreateProcessArgumentModifier modifier) = 0;
     virtual void setNativeArguments(const QString &arguments) = 0;
 #endif
 
@@ -152,6 +154,7 @@ protected:
     ProcessMode processMode() const { return m_processMode; }
 private:
     const ProcessMode m_processMode;
+    bool m_belowNormalPriority = false;
 };
 
 class ProcessHelper : public QProcess
@@ -218,6 +221,8 @@ public:
     {
         m_processStartHandler.setProcessMode(processMode());
         m_processStartHandler.setWriteData(writeData);
+        if (isBelowNormalPriority())
+            m_processStartHandler.setBelowNormalPriority(&m_process);
         m_process.start(program, arguments, m_processStartHandler.openMode());
         m_processStartHandler.handleProcessStart(&m_process);
     }
@@ -265,8 +270,6 @@ public:
     { m_process.m_disableUnixTerminal = true; }
 
 #ifdef Q_OS_WIN
-    void setCreateProcessArgumentsModifier(QProcess::CreateProcessArgumentModifier modifier) override
-    { m_process.setCreateProcessArgumentsModifier(modifier); }
     void setNativeArguments(const QString &arguments) override
     { m_process.setNativeArguments(arguments); }
 #endif
@@ -319,7 +322,11 @@ public:
     { m_handle->setProcessEnvironment(environment); }
     void setWorkingDirectory(const QString &dir) override { m_handle->setWorkingDirectory(dir); }
     void start(const QString &program, const QStringList &arguments, const QByteArray &writeData) override
-    { m_handle->start(program, arguments, writeData); }
+    {
+        if (isBelowNormalPriority())
+            m_handle->setBelowNormalPriority();
+        m_handle->start(program, arguments, writeData);
+    }
     void terminate() override { cancel(); } // TODO: what are differences among terminate, kill and close?
     void kill() override { cancel(); } // TODO: see above
     void close() override { cancel(); } // TODO: see above
@@ -345,8 +352,6 @@ public:
     void setDisableUnixTerminal() override { QTC_CHECK(false); }
 
 #ifdef Q_OS_WIN
-    void setCreateProcessArgumentsModifier(QProcess::CreateProcessArgumentModifier modifier) override
-    { QTC_CHECK(false); }
     void setNativeArguments(const QString &arguments) override { QTC_CHECK(false); }
 #endif
 
@@ -619,12 +624,7 @@ void QtcProcess::start()
             command = QCoreApplication::applicationDirPath()
                     + QLatin1String("/qtcreator_ctrlc_stub.exe");
         } else if (d->m_process->lowPriority()) {
-#ifdef Q_OS_WIN
-            d->m_process->setCreateProcessArgumentsModifier(
-                [](QProcess::CreateProcessArguments *args) {
-                    args->flags |= BELOW_NORMAL_PRIORITY_CLASS;
-            });
-#endif
+            d->m_process->setBelowNormalPriority();
         }
         ProcessArgs::addArgs(&args, arguments.toWindowsArgs());
 #ifdef Q_OS_WIN
diff --git a/src/tools/processlauncher/launchersockethandler.cpp b/src/tools/processlauncher/launchersockethandler.cpp
index 81a07c2b082..2e0ef6b08e9 100644
--- a/src/tools/processlauncher/launchersockethandler.cpp
+++ b/src/tools/processlauncher/launchersockethandler.cpp
@@ -243,6 +243,8 @@ void LauncherSocketHandler::handleStartPacket()
     ProcessStartHandler *handler = process->processStartHandler();
     handler->setProcessMode(packet.processMode);
     handler->setWriteData(packet.writeData);
+    if (packet.belowNormalPriority)
+        handler->setBelowNormalPriority(process);
     process->start(packet.command, packet.arguments, handler->openMode());
     handler->handleProcessStart(process);
 }