Perl写入文件的效率

Question

I am creating a database with some informations of files.
eg: file_name | size | modify_date ...

I was thinking what is more efficient in this situation:

1) For each file get the info and print them in my file

foreach my $file ( @listOfFiles) {                 
    my %temporary_hash = get_info_for_file($file); //store in a tempoarary hash
                                                     the informations for current file
    print_info(%temporary_hash, $output_file);     // print the  information in my output file
}

2) Store the info for every file in a hash and print all the hash at once

foreach my $file( @listOfFiles){
    store_info_in_hash( get_info_for_file($file), %hash); // for each file, store the 
                                                             information in a global hash

   }
print_all_info(%hash, $output_file);                       //after i have informations for each file
                                                             print the whole hash in my output file 

Answer 1

You are wrong to consider efficiency before you have even got your program working

You should write your code as clearly as possible and debug it. Only then, if it is not running fast enough for your purpose, you should put your code through a profiler to discover the bottlenecks that are taking the most time

The two options you show will probably not be very different unless your files are enormous

Answer 2

Doing a benchmark test on the two options i got those results ( which, if I increase the information size for each file, will lead to even bigger differencies between the two).