For what its worth:
I was unhappy about your benchmark, since the two types of code did not appear to be the same:
@arr1 = map { push @arr1, ($_+ 2) } @data;

[download]
in particular seemed suspect to me. Also the order of memory allocation can affect benchmarks. When I ran the supplied code the foreach loop worked fine (5 seconds on my machine) but the map gave Out of memory!.

So I rewrote each part to be a subroutine, and tided the map so it looked like this:
sub mapsub {
    my @arr;
    
    @arr = map { ($_ + 2) } @data;
}

[download]
I can't say if that was faster, because it still gives Out of memory! Must be something to do with a temporary list (5.10.1 on Windows). Reducing the size of @data by a factor of 10 gives map taking around twice as long, and each taking under a second.

In reply to Re^3: Map Vs Foreach by cdarke
in thread Map Vs Foreach by perlCrazy

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