I think this takes less time for process
If U wish please try this

undef $/;
open (FH, "D:\\temp.txt") || die "Couldn't  open file: $!";
@required=();
$str=<FH>;
close(FH);
(@arr)=$str=~m#(abcde.*?PARTNAME)#gsi;
print "$_\n" for @arr;
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