You can transform @arraytocompare to a hash as you can see below. Hash key lookup is very effective. 
my $hashtocompare{$_}++ for (@arraytocompare);

foreach my $strfile (@tempfiles) {
    push @newarray, $strfile unless exists $hashtocompare{$strfile};
}

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In reply to Re: improve performance by pme
in thread improve performance by swissknife

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