Now as I have only 5 thread created I expect to have only 5 instance of tar and similarly 5 instance of gzip. But that doesn't seems to be the case.

You say that, and indeed you do start out with my $numThreads = 5;; but then, you immediately override that: 

     if ( $totalKeys le $numThreads ) {
         $numThreads = $totalKeys;
     }

[download]

And then, in the loop where you create your threads you don't seem to use that variable at all:

    for my $href (@arrHash) {
         my $t = threads->create( \&Thread, \%$href, $sourcePath,
             $destinationPath );
         push( @arrThreads, $t );
     }

[download]

Your has nothing to do with backticks not blocking, but is simply a programming error in that you are just starting lots and lots of threads without (it appears) any mechanism to control how many you start.

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In reply to Re^3: How to make a thread to wait till a command on shell get completed. by BrowserUk
in thread How to make a thread to wait till a command on shell get completed. by techman2006

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