Gearman is a distributed processing framework that allows work to be distributed to multiple machines and workers. The document discusses setting up Gearman and using it to distribute tasks like image resizing. It explains how to create Gearman workers to handle tasks, create clients to submit tasks, and get status updates on task processing. It also covers error handling, managing workers, and scaling the system by adding more workers.

1. Dominik Jungowski / CHIP Xonio Online GmbH
Distributed work with
Gearman

2. Law of two feet

3. Dominik Jungowski
27 years old
ScrumMaster at CHIP Online
Psychology student at Fernuni
Hagen

4. Topics
What is Gearman?
Setting up Gearman
Basic Usage
Job status
Error handling
Managing workers

5. What is Gearman?

7. Script Processing Script (cont.)

8. Script Processing Script (cont.)

9. Worker
Script Worker
Worker

10. Setting up Gearman server
latest version: 0.24

11. aptitude install gearman-job-server

12. Setting up PECL Extension

13. pecl install channel://pecl.php.net/gearman-0.8.0.tgz

14. extension=gearman.so

15. user@server:~# gearmand

16. Basic Usage

17. Worker

18. $worker = new GearmanWorker();
$worker->addServer();
$worker->addFunction(
‘imageResize‘,
array($image, ‘resize‘)
);
while($worker->work()) {
}

19. $worker = new GearmanWorker();
$worker->addServer();
$worker->addFunction(
‘imageResize‘,
array($image, ‘resize‘)
);
while($worker->work()) {
}

20. $worker = new GearmanWorker();
$worker->addServer();
$worker->addFunction(
‘imageResize‘,
array($image, ‘resize‘)
);
while($worker->work()) {
}

21. $worker = new GearmanWorker();
$worker->addServer();
$worker->addFunction(
‘imageResize‘,
array($image, ‘resize‘)
);
while($worker->work()) {
}

22. $worker = new GearmanWorker();
$worker->addServer();
$worker->addFunction(
‘imageResize‘,
array($image, ‘resize‘)
);
while($worker->work()) {
}

23. namespace Cxo;
class Image
{
public function resize(GearmanJob $job)
{
$tmpFile = $job->workload();
// Resizing takes place here
...
return $finalFileName;
}
}

24. namespace Cxo;
class Image
{
public function resize(GearmanJob $job)
{
$tmpFile = $job->workload();
// Resizing takes place here
...
return $finalFileName;
}
}

25. namespace Cxo;
class Image
{
public function resize(GearmanJob $job)
{
$tmpFile = $job->workload();
// Resizing takes place here
...
return $finalFileName;
}
}

26. namespace Cxo;
class Image
{
public function resize(GearmanJob $job)
{
$tmpFile = $job->workload();
// Resizing takes place here
...
return $finalFileName;
}
}

27. Synchronous Jobs

28. $client = new GearmanClient();
$client->addServer();
$client->do('imageResize', '/tmp/someimage.jpg');

29. $client = new GearmanClient();
$client->addServer();
$client->do('imageResize', '/tmp/someimage.jpg');

30. $client = new GearmanClient();
$client->addServer();
$client->do('imageResize', '/tmp/someimage.jpg');

31. $client = new GearmanClient();
$client->addServer();
$client->do('imageResize', '/tmp/someimage.jpg');

32. $client->doHigh();

33. $client->do() returns worker result

34. Asynchronous Jobs

35. $client->doBackground(
'imageResize',
'/tmp/someimage.jpg'
);

36. $client->doBackground() returns job handle

37. Tasks

38. $client->addTask(
'imageResize',
'/tmp/someimage.jpg'
);

39. $client->addTaskBackground(
'imageResize',
'/tmp/someimage.jpg'
);

40. $client->runTasks();

41. Scale by adding more workers
(as long as you‘re not running jobs synchronously)

43. Script Processing Script (cont.)

44. Processing
Script Processing Script (cont.)
Processing

45. Job status

46. $handle = $client->doBackground();

47. $status = $client->jobStatus($handle);

48. array(4) {
[0]=> bool(true) // Is the job known?
[1]=> bool(true) // Is the job running?
[2]=> int(4) // Numerator
[3]=> int(10) // Denominator
}

49. $job->sendStatus(4, 10);

50. Error handling

51. GEARMAN_SUCCESS

52. GEARMAN_WORK_FAIL

53. $worker->returnCode();

54. $client->returnCode();

55. $job->sendFail();

56. $job->sendWarning(‘Something went wrong‘);

57. $job->sendException(‘Something went wrong‘);

58. $message = $client->do();

59. Managing workers

60. supervisord

61. Memory consumption

62. Persistence

63. “Whuh?“

64. $client->doJobHandle();
doesn‘t do what it should - and many more functions as well

65. GearmanClient::setOptions
Return Values: Always returns TRUE

66. do is a keyword

67. Thank you!
joind.in: http://joind.in/3907
Twitter: @djungowski
Blog: www.phpdevblog.net