As others have said, jamming 3G of data into 1G of ram is going to be problematic ... especially since you're doubling your amount of memory by reading the file into memory first. I would recommend:

  1. processing the file line by line 
      open( my $fh, "<", $sigDataFile ) || die( "cannot open file - $!" );
  while( <$fh> ) {
     chomp;
     my( $key, $value ) = split(/=/, $_); # does = need to be escaped?
     ...
   }

    [download]
  2. use something like SDBM_File or GDBM_File 
      use Fcntl;
  use SDBM_File;

  tie( %hash, 'SDBM_File', 'temp_file_name', O_RDWR|O_CREAT, 0666 )
    or die "Couldn't tie SDBM file 'filename': $!; aborting";

  open( my $fh, "<", $sigDataFile ) || die( "cannot open file - $!" );
  while( <$fh> ) {
    chomp;
    my( $key, $value ) = split( /=/, $_ );
    $hash{$key} = $value;
    ...
  }

    [download]

-derby

In reply to Re: Memory issue while opening and reading a file by derby
in thread Memory issue while opening and reading a file by koti688

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