profiling.qdoc

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// Copyright (C) 2026 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
 
/*!
\page qtquick-profiling.html
\ingroup qtquick-tools
\title Profiling QML Applications
\brief Provides information on how to use QML's profiling tools.
 
\section1 QML Profiler
 
With the \l{\QC: Profiling QML Applications}{QML Profiler} you can analyze
your QML code for performance issues. The profiler is part of
both \QC and \QDS. The best way to use it is to utilize \QC or \QDS
defaults for build and run settings.
 
\QVSC also includes a \l{\QVSC: Profile QML code}{QML Profiler}.
 
If you are building or running manually, in order to use the QML Profiler,
you need to enable the \l{QML debugging infrastructure}.
 
\section1 Using the command line qmlprofiler tool
 
Qt provides the \l{qmlprofiler} command line tool to capture profiling data in a
file. The file can later be loaded into \QC or \QDS for analysis. It
\l{Connecting to applications}{connects} to the application using the
debugging protocol.
 
To run this tool, after starting the application with the
\l{QML debugging infrastructure} enabled, enter the following command:
 
\c {qmlprofiler -p <port> -attach <ip address>}
 
It is advisable to use the \c{services} argument to \c{-qmljsdebugger} in order to
limit the debug infrastructure to only the services required. These are typically
\c{CanvasFrameRate}, \c{EngineControl}, and \c{DebugMessages}. Having other services
enabled may influence the profiling results.
 
*/