Beefy Boxes and Bandwidth Generously Provided by pair Networks
more useful options
 
PerlMonks  

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??

Hi JediWombat,

The following provides a parallel demonstration to process all 3 LDIF files simultaneously. It requires MCE 1.830 minimally due to MCE::Relay failing from setting the input separator. That said, am posting the code before releasing 1.830 in order to have the perlmonks URL for the changelog.

Well, here is the code.

#!/usr/bin/perl use strict; use warnings; # Requires MCE 1.830. Fixes MCE::Relay stalling from setting $/. use MCE::Loop 1.830; my $mbnum = $ARGV[0] or die "usage: $0 mbnum\n"; my @ldif_files = qw( /path/to/file1.ldif.bz2 /path/to/file2.ldif.bz2 /path/to/file3.ldif.bz2 ); MCE::Loop->init( max_workers => scalar @ldif_files, chunk_size => 1, init_relay => '' ); mce_loop { # my ($mce, $chunk_ref, $chunk_id) = @_; # When chunk_size 1 is specified, $_ contains # the same value as $chunk_ref->[0]. my ($file, $ret) = ($_, ''); # Must localize $/ to not stall MCE, fixed in 1.830. # Localizing $/ is recommended, but fixed MCE if not. local $/ = ""; open my $fh, "-|", "/usr/bin/bzcat $file" or warn "open error ($file): $!"; if (defined fileno($fh)) { while (<$fh>) { if (/uid=$mbnum/m) { $ret = "## $file\n"; $ret .= $_; last; } } close $fh; } # Relay is beneficial for running a code block serially # and orderly. The init_relay option enables MCE::Relay. # All participating workers must call relay. Here, workers # write to STDOUT orderly starting with chunk_id 1. MCE::relay { print $ret }; } \@ldif_files; MCE::Loop->finish;

MCE 1.830 will be released on CPAN no latter than Monday, the 7th of August. In the meantime, the MCE Github repository is current.

Regards, Mario


In reply to Re^5: Searching large files a block at a time by marioroy
in thread Searching large files a block at a time by JediWombat

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others examining the Monastery: (6)
As of 2021-11-30 15:54 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found

    Notices?