Slurping, splitting on \n, then adding in the \n is the exact same as:

my @records = <BIGFILE>;
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Why not just do that? In fact, you could do something like:

my $searchstring = 'LONDON';
my @records = grep /$searchstring/, <BIGFILE>;
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Voila! Just the string you want in @records, all postpended with \n. :)

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