This takes too long to process. Please tell me how can this be optimised.
Below is the sample lines attached. 
99.60.97.205    -       -       [26/Mar/2011:06:00:00   +0000]  GET /2
+009-03-29/world/impact.row.atlantic_1_rower-paul-ridley-cancer-resear
+ch?_s=PM:WORLD HTTP/1.1      200     9386    www.abc.com     Mozilla/
+5.0 (Macintosh; U; Intel Mac OS X 10_6_6; en-US) AppleWebKit/534.13 (
+KHTML, like Gecko) Chrome/9.0.597.107 Safari/534.13        TCP_MISS  
+      Apache=-        -       1068000 -       -       -       deflate
+=-       rmt=-
72.234.67.132   -       -       [26/Mar/2011:09:00:00   +0000]  GET /a
+d-abc.php?f=medium_rectangle HTTP/1.1     200     869     www.abc.com
+     Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.1.
+16) Gecko/20101130 Firefox/3.5.16       TCP_HIT Apache=-        -    
+   1000    -       -       -       deflate=-       rmt=-
68.12.178.167   -       -       [26/Mar/2011:09:00:00   +0000]  GET /a
+d-feedback.js.php?e3e999d9b79cf36c165f5b379a0e9f269be82344 HTTP/1.1  
+     200     600     www.abc.com     Mozilla/4.0 (compatible; MSIE 8.
+0; Windows NT 5.1; Trident/4.0; GTB6.6; .NET CLR 2.0.50727; .NET CLR 
+3.0.4506.2152; .NET CLR 3.5.30729) TCP_HIT Apache=-        -       10
+00    -       -       -       deflate=-       rmt=-

[download]
The file size is 16955714940 bytes. 
#!/usr/bin/perl
use strict;
use warnings;
use Date::Manip;
my $n="4";
my $date_converted = UnixDate(ParseDate("$n days ago"),"%e/%h/%Y");
open FILE,"> file.txt";
open DATA,"input.txt";

while(<DATA>){
my @tab_delimited_array = split(/\t/,$_);
  $tab_delimited_array[3] =~ s/^\[//;
  $tab_delimited_array[3] =~ s/^\-//;
        my $converted_date = Date_ConvTZ( UnixDate($tab_delimited_arra
+y[3],"%Y%m%d%H:%M:%S"),'GMT','PST');
        my $pst_converted_date = UnixDate($converted_date,"%e/%h/%Y:%H
+:%M:%S");
        $pst_converted_date =~ s/^\s//g;
        my $extracted_YMD=UnixDate($converted_date,"%e/%h/%Y");
        if($extracted_YMD =~ m/$date_converted/){
        print FILE $_;
        }
}

close FILE;
close DATA;

[download]

In reply to Optimise the script by Anonymous Monk

Title:
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