Beefy Boxes and Bandwidth Generously Provided by pair Networks
Just another Perl shrine

comment on

( [id://3333] : superdoc . print w/replies, xml ) Need Help??

(*)Updated units per pc88mxers post below.

By serialising the counts through a threaded udp server, batching them on input before transfering them to the background writing thread, I managed sustained throughput rates of close to 600k/minute on a single core 2.6 M*GHz machine running both producer and consumer, and with half the bandwidth taken up with a download going on simultaneously:

Consumer run:

c:\test> -MAXBUF=500 Total: 347176 throughput: 9777/sec [max: 9987]

MAXBUF=500 seems to be about the sweet spot on my machine. I can get higher throughputs by upping the priority of the server process. I was just writing the counts out to a file in the background, but you could probably do batch updates to a db without slowing things much.


use strict; use threads; use threads::shared; use Thread::Queue; use Time::HiRes qw[ time usleep ]; use IO::Socket; use List::Util qw[ max ]; $|++; our $PORT ||= 9999; our $FILE ||= 'theLog'; our $LEN ||= 6; our $MAXBUF ||= 1000; my $Q = new Thread::Queue; open my $log, '+> :raw', $FILE or die "$FILE: $!"; my $start = time; my $n :shared = 0; my %log; my $total = 0; async { my $max = 0; my $thru = 0; while( my $in = $Q->dequeue ) { ++$log{ $_ } for split chr(0), $in; sysseek $log, 0, 0; my $logRec = join "\n", map{ $_ . ':' . $log{ $_ } } sort keys + %log; syswrite( $log, $logRec ); $max = max( $max, $thru = int( $n / ( time() - $start ) ) ); printf "\r\t Total: %8d throughput: %5d/sec [max:%5d]", $total, $thru, $max; $total += $n; $n = 0; $start = time(); sleep 1; } }; my $srv = IO::Socket::INET->new( LocalPort => $PORT, Proto => 'udp', ) or die "Socket: $@ : [$^E]"; my $buffer = ''; my $msg; while( $srv->recv( $msg, $LEN ) ) { next unless length $msg; $n++; if( length( $buffer .= chr(0) . $msg ) > $MAXBUF ) { $Q->enqueue( $buffer ); $buffer = ''; } }


#! perl -slw use strict; use IO::Socket; our $N ||= 1000; our $PORT ||= 9999; our $DELAY ||= 0.0001; my $sock = IO::Socket::INET->new( Proto => 'udp', PeerPort => $PORT, PeerAddr => 'localhost' ) or die "$@ [$^E]"; my $sent = 0; for ( 1 .. $N ) { ++$sent; $sock->send( int rand( 32767 ) ); select undef,undef, undef, $DELAY; } print "Sent: $sent";

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Multiple write locking for BerkeleyDB by BrowserUk
in thread Multiple write locking for BerkeleyDB by dino

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 How to display code and escape characters are good places to start.