Upgrading from PHP 5.3 to 5.5

A small talk on the experiences gained from migrating from PHP 5.3 to 5.5.

Transcript

2. Glen Mailer
3. The Codebase
4. First commit April 2010
 60k commits since
5. 9300 PHP files
 690k lines of code According to git and cloc
6. 10 releases a week
 35 active committers
 10 concurrent streams
 1 deployable
7. The Platform
8. 8 Test Environments
 1 Staging Environment
 2 Live Environments
9. 74 Live PHP boxes
10. 1300 req/s peak
 500k uniques/week
11. Why?
12. Using basically the same PHP version as the first commit with security patches
13. PHP 5.3 is dead
14. Bug fixes
 Performance
15. New Features! short array syntax traits $this in closures yield finally
16. but no smoking gun
17. Bug #64827
 GC causes segfaults
18. The Plan
19. Upgrade a dev box
 Support 5.3 and 5.5
 Pass all tests
 Upgrade 1 Test env
 Upgrade CI
 Upgrade Test & Staging
 Incrementally Upgrade Live
20. Vagrant
 Chef
 Unit Tests
 Acceptance Tests
21. Hack hack hack...
22. 3 days later
23. What changed?
24. APC
 becomes
 OPcache and APCu
25. Check for new function, fall back to old one if (function_exists('opcache_reset')) { opcache_reset(); } else { apc_clear_cache(); }
26. “The PHP api will retain compatibility with APC, as will common configuration options, providing a drop in replacement.” APCu
27. Not a drop in replacement
28. APCu 4.0.1
 APCu 4.0.2
29. No more
 mysql_
30. It will not be missed
31. preg_replace /e
 becomes
 preg_replace_callback
32. (string) array()
 Now raises a warning Still returns “Array”
33. Type-checked function function inc($int) { if (!is_int($int)) { throw new InvalidArgumentException( 'Expected int, got: ' . $int ); } return $int + 1; }
34. Unit test for type-checked function /** * @dataprovider provideIncInvalid */ function testIncRejectsInvalid($a) { try { inc($a); $this->fail('Expected exception'); } catch (InvalidArgumentException $ex) {} } function provideIncInvalid() { return array( null, true, "string", array() ); }
35. Simplest fix throw new InvalidArgumentException( 'Expected int, got: ' . json_encode($int) );
36. $a = "string”;
 $a['index'];
 Now raises a warning
37. // protected $a;
 ++$this->a
 Now raises a warning
38. Progress
39. Upgrade a dev box
 Support 5.3 and 5.5
 Pass all tests
 Upgrade 1 Test env
 Upgrade CI
 Upgrade Test & Staging
 Incrementally Upgrade Live
40. Upgrade a dev box
 Support 5.3 and 5.5
 Pass all tests
 Upgrade 1 Test env
 Upgrade CI
 Upgrade Test & Staging
 Incrementally Upgrade Live
41. What now?
42. Finish Migrating Live
43. See if the hard to reproduce failures have stopped
44. Start using new features!
45. Keep up to date
46. You should upgrade too!
47. Fin.
48. Questions?
49. @glenathan https://joind.in/9473