Hello,everyone! I am developping an crawler program, my process is as follow:

CentOS Linux release 7.2.1511(Core)

This is perl 5, version 20, subversion 3 (v5.20.3) built for x86_64-linux

Now I use BerkeleyDB module to store the URL queue, the script is able to work, but the efficiency is not high.Because when I use multiple script to read the database db, I found multiple script can't read at the same time . They were blocked. After completing the script will turn to a script.

There is a question: I need to store the URL queue in the file database, not the memory, what module is the non blocking, simple and efficient ?

I want to read to a URL from the database ,and this URL will deleted immediately , or lock the URL not to be read by other script at the same time, thank you!

In reply to The question of URL queue selection module ? by Perl_Love

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