php-bencode is a PHP Bencode extension which supports encoding, decoding, and editing Bencode strings or files. The previous version of php-bencode, which supports PHP 5, needs PHP-CPP to run while the new one now requires no external libraries.

The location of the source code remains the same, on both GitHub and my personal GitLab instance:
https://github.com/Frederick888/php-bencode
https://git.tsundere.moe/Frederick888/php-bencode

Written in C/C++, php-bencode offers a great performance boost for Bencode manipulations. I did a benchmark on different implementations by decoding a Bencode file with 1M sub-nodes in my box (8 cores, 1G memory). The sample file can be downloaded here: Bencode Sample.

According to the results, php-bencode was able to finish decoding in a significantly shorter time. The memory usage was a little higher than that of the pure PHP library, but I reckon it’s an acceptable trade-off for type safety. (For example, if the original Bencode file contains an empty dictionary or list, data loss may happen after decoding and re-encoding using the pure PHP library.)

Still, there’s much work to do. The previous version supported getting/setting a node by path and searching through the whole tree, which have not been implemented in the new one yet. Additionally, the new php-bencode supports only PHP 7 for now and I’m considering to support PHP 5.6 as well.

php-bencode (decoding to objective array)			
start            end              usage      duration
1463911318.9625  1463911319.2908  235060168  0.3283
1463911319.3859  1463911319.6992  235060168  0.3133
1463911319.7819  1463911320.1416  235060168  0.3598
1463911320.2392  1463911320.5557  235060168  0.3165
1463911320.6376  1463911320.9569  235060168  0.3194
1463911321.0616  1463911321.3757  235060168  0.3142
1463911321.4570  1463911321.7702  235060168  0.3132
1463911321.8663  1463911322.2208  235060168  0.3545
1463911322.3028  1463911322.6624  235060168  0.3595

Pure PHP Library (PHP 7.0.1, decoding to plain array)			
start            end              usage      duration
1463911300.8234  1463911301.4810  191506800  0.6576
1463911301.4991  1463911302.1591  191506800  0.6600
1463911302.1837  1463911302.7704  191506800  0.5866
1463911302.7883  1463911303.4514  191506800  0.6631
1463911303.4758  1463911304.1296  191506800  0.6538
1463911304.1479  1463911304.7430  191506800  0.5951
1463911304.7675  1463911305.3909  191506800  0.6235
1463911305.4093  1463911306.0353  191506800  0.6259
1463911306.0667  1463911306.6656  191506800  0.5990
1463911306.6834  1463911307.3495  191506800  0.6661 

Pure PHP Library (PHP 5.6.16, decoding to plain array)			
start            end              usage      duration
1463911241.9759  1463911244.9670  255799264  2.9912
1463911245.1560  1463911247.8958  255705392  2.7398
1463911248.0932  1463911250.8363  255776296  2.7430
1463911251.0001  1463911253.8623  255738160  2.8623
1463911254.0313  1463911256.8981  255724336  2.8668
1463911257.0905  1463911259.8378  255707600  2.7473
1463911260.0006  1463911262.8360  255766880  2.8354
1463911262.9939  1463911265.8042  255790648  2.8103
1463911265.9561  1463911268.6946  255756520  2.7385
1463911268.8425  1463911271.7020  255781160  2.8595

 

<?php
printf("start\tend\tusage\tduration\n");
for ($i = 0; $i < 20; $i++) {
    $time1 = microtime(true);
    if ($i >= 11)
        printf("%.4f\t", $time1);
    $broot = bitem::load('performance.dat');
    $time2 = microtime(true);
    if ($i >= 11)
        printf("%.4f\t%d\t%.4f\n", $time2, memory_get_usage(), $time2 - $time1);
    unset($broot);
}

 

<?php
require 'torrent-bencode/src/Bhutanio/BEncode/BEncode.php';

printf("start\tend\tusage\tduration\n");
for ($i = 0; $i < 20; $i++) {
    $bcoder = new Bhutanio\BEncode\BEncode;
    $time1 = microtime(true);
    if ($i >= 10)
        printf("%.4f\t", $time1);
    $broot = $bcoder->bdecode_file('performance.dat');
    $time2 = microtime(true);
    if ($i >= 10)
        printf("%.4f\t%d\t%.4f\n", $time2, memory_get_usage(), $time2 - $time1);
    unset($broot);
    unset($bcoder);
}