profiling in QTCreator

I am absolutely new to profiling in QTCreator.
Here is what I am doing:

1) Set the build to Release mode
2) Analyze>QML Profiler>Start
It is showing error:

Code:

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Could not connect to the in-process QML profiler.
Do you want to retry?

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Even after retrying nothing happening
3) Analyze>Valgrind Memory Analyzer>Start
error:

Code:

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Analyzing memory of /home/hls/Grab-build-desktop-Qt_4_8_1_in_PATH__System__Release/Grab
** Error: "valgrind" could not be started: No such file or directory **
** Analyzing finished **

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I checked physically,the executable file Grab is there in the above said directory
4) Analyze>Valgrind Function profiler>Start
error:

Code:

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You are trying to run the tool "Valgrind Function profiler" on an application in Debug mode.The tool is designed to be used in Release mode

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I am using it in release mode only.

I guess I am missing some configuration.Can someone tell what I am missing?

I have solved the issue,had to install 'valgrind' externally.