jami / SPW

PHP SPW - Simple Process Wrapper

SPW - Simple process wrapper

The process wrapper is a lightweight implementation for async processhandling. Today (2013) it is still a pain in the arse to get php zts with pthreads support. A simple workaround for that problem is to split threadlogic up to worker scripts and execute them parallel.

Example 1:

$spw = new ProcessWrapper('php');
$spw->setInput('<?php echo "1234567"; ?>');
$spw->start();

// do stuff

// wait for process end
$spw->wait();
$outputBuffer = $spw->getOutput();

Example 2:

$processQueue = new ProcessQueue();

// in sum 10 seconds sequential processing time
// parallel it should take as long as the duration of the slowest process

$cmd1 = "sleep 2; echo 'cmd1 1';";
$cmd2 = "sleep 4; echo 'cmd2 1';";
$cmd3 = "sleep 2; echo 'cmd3 1'; sleep 2";

$processQueue->attachProcess(new ProcessWrapper($cmd1));
$processQueue->attachProcess(new ProcessWrapper($cmd2));
$processQueue->attachProcess(new ProcessWrapper($cmd3));

$processQueue->wait();

$this->assertEquals(
    4.0,
    $processQueue->getProcessTime(),
    'This queue should take 4.0 seconds to process',
    0.1
);

Try the demo

The DownloadClient.php demo use the ProcessQueue to spawn N download worker processes. Each process downloads a part of the target file. For this task it use curl and range headers. In the example below we download the 229MiB File install-amd64-minimal-20131010.iso with 30 workers.

cd ./SPW/Demo
php DownloadClient.php "http://distfiles.gentoo.org/releases/amd64/autobuilds/current-iso/install-amd64-minimal-20131010.iso" 30
> Attach worker process for range 0-7969177
> Attach worker process for range 7969177-15938354
> Attach worker process for range 15938354-23907531
> Attach worker process for range 23907531-31876708
> Attach worker process for range 31876708-39845885
> Attach worker process for range 39845885-47815062
> Attach worker process for range 47815062-55784239
> Attach worker process for range 55784239-63753416
> Attach worker process for range 63753416-71722593
> Attach worker process for range 71722593-79691770
> Attach worker process for range 79691770-87660947
> Attach worker process for range 87660947-95630124
> Attach worker process for range 95630124-103599301
> Attach worker process for range 103599301-111568478
> Attach worker process for range 111568478-119537655
> Attach worker process for range 119537655-127506832
> Attach worker process for range 127506832-135476009
> Attach worker process for range 135476009-143445186
> Attach worker process for range 143445186-151414363
> Attach worker process for range 151414363-159383540
> Attach worker process for range 159383540-167352717
> Attach worker process for range 167352717-175321894
> Attach worker process for range 175321894-183291071
> Attach worker process for range 183291071-191260248
> Attach worker process for range 191260248-199229425
> Attach worker process for range 199229425-207198602
> Attach worker process for range 207198602-215167779
> Attach worker process for range 215167779-223136956
> Attach worker process for range 223136956-231106133
> Attach worker process for range 231106133-239075328
> Downloaded 239075328 bytes in 39.25455904007s

Imho 39 seconds is really fast. If I download the file with wget i have to wait 7m49s

Running tests

cd ./SPW
curl -sS https://getcomposer.org/installer | php
php composer.phar install
phpunit