use File::ReadBackwards;
use strict;
use autodie;
use File::stat;
my $file = 'D:/service_console.log';
my $bw = File::ReadBackwards->new($file);
while (defined ( my $log_line = $bw->readline))
{  for( my $n=0; $<=3; $n++)
   {
    my $size = stat($file)->size;
    sleep(60);
    my $size = stat($file)->size;
    last if ( $size1 == $size2);
    }
    push (my @array, $log_line);
   for (@array)
   { last if (/ running mode/);}
}$bw->close();