Hitting the Turbo Button: Upgrading to PHP 7 at Etsy

PHP 7 offers fantastic resources to developers, trims memory consumption substantially, and can significantly reduce the CPU usage your software requires–often with few changes to your code. For those looking to migrate to PHP 7 or unsure of best practices to incorporate into your upgrade, you’ll learn about a battle tested design for deployment at scale. In this talk, I’ll discuss how Etsy designed a core upgrade to the site and how that might be applicable to companies of all sizes. Discussions will include how we chose between Hack/HHVM and PHP 7 and some of the tools built along the way, such as Phan, an open source static analyzer. This will also include an in depth review of how we deployed the upgrade, detailing some of the bumps in the process. Attendees should come away with a strong foundation of how the next phase of PHP can drastically improve performance and add powerful new features to aid in development.

Transcript

1. 1
   
   Hitting the Turbo Button:
   Upgrading to PHP 7 at
   Etsy
   @wcgallego
   

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2. 2
   Hey, I’m Will!
   Ops Engineer @ Etsy
   @wcgallego
   

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3. 3
   @wcgallego
   

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4. 4
   
   Roadmap
   •Brief history of PHP 5 point release upgrades at
   Etsy
   •Our use of HHVM
   •Deciding between Hack/HHVM vs. PHP 7
   •Deployment of PHP 7
   •Wins, pitfalls, and features in PHP 7
   @wcgallego
   

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5. 5
   #VUNPTUJNQPSUBOUMZ
   *XBOUZPVUPCFTVDDFTTGVMBU
   VQHSBEJOH1)1
   @wcgallego
   

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6. 6
   PHP @ Etsy Timeline
   @wcgallego
   Prehistory 2012 2013 2014 2015 …
   2012
   …to 5.3
   PHP 5.2
   2013
   …to 5.4
   2014
   …to 5.5
   2015
   …5.6?
   

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7. Reworking our
   API Architecture
   @wcgallego
   

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8. 8
   @wcgallego
   Webs
   Browser
   DBs
   Previous Approach
   

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9. 9
   @wcgallego
   Webs
   Browser
   Internal API
   (multicurl)
   API Node API Node API Node
   API First Approach
   DBs
   

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10. 10
    @wcgallego
    Rising API Requests
    

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11. HHVM to the rescue!
    @wcgallego
    

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12. 12
    @wcgallego
    

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13. 13
    @wcgallego
    

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14. 14
    @wcgallego
    

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15. 15
    PHP @ Etsy Timeline
    @wcgallego
    Spring

    2015
    Summer

    2015
    Fall

    2015
    January

    2016
    February

    2016
    Summer

    2016
    Early PHP 7 Testing/Benchmarks
    

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16. 16
    https://wiki.php.net/rfc/php6
    “Version 6 is generally associated with failure in
    the world of dynamic language”
    @wcgallego
    Wait…what happened to PHP 6?
    

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17. 17
    PHP @ Etsy Timeline
    @wcgallego
    Spring

    2015
    Summer

    2015
    Fall

    2015
    January

    2016
    February

    2016
    Summer

    2016
    Porting Etsy Extensions to PHP 7
    

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18. 18
    https://bugs.php.net/bug.php?id=72396
    @wcgallego
    https://php-lxr.adamharvey.name/source/
    http://lxr.php.net/
    

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19. 19
    
    1)1WT)BDL))7.

    8IJDIEPXFDIPPTF
    @wcgallego
    

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20. 20
    http://talks.php.net/velocity15#/wpbench
    http://hhvm.com/blog/9293/lockdown-results-and-hhvm-performance
    https://kinsta.com/blog/the-definitive-php-7-final-version-hhvm-
    benchmark/
    @wcgallego
    

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21. 21
    Hack/HHVM
    @wcgallego
    Cons
    •More experiential knowledge with

    PHP/mod_php than Hack/HHVM/
    fastcgi
    •Debugging multithreaded extensions
    •Different environment than
    Facebook: multi-curl in API at Etsy
    vs. async at Facebook
    •HHVM deploy shorter, but Hack
    everywhere a multiyear project
    Pros
    •Async (cooperative multitasking)
    •Generics
    •Collections (Vectors, Maps, Sets, Pairs)
    •Tuples, Enums, Shapes
    •compile time features like void return
    

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22. 22
    PHP 7
    @wcgallego
    Cons
    •Need to write our own static analyzer
    •Core not yet prod ready
    •Extensions hadn’t seen wide internal
    testing like core
    •Some type features Hack has not in
    PHP
    Pros
    •All of our editors supported PHP 7 - vim,
    emacs, sublime text, phpstorm, etc.
    •Unsure direction Facebook takes Hack
    •Maintain current understanding of how
    our site runs
    •Shorter migration
    •Rasmus
    

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23. 23
    PHP @ Etsy Timeline
    @wcgallego
    Spring

    2015
    Summer

    2015
    Fall

    2015
    January

    2016
    February

    2016
    Summer

    2016
    Decision to deploy PHP 7
    

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24. 24
    4
    2
    1 3
    Staging
    Fix Tests 100% Dev
    Compatible with
    PHP 5 and PHP
    7 code, still
    running PHP 5
    Test PHP 7
    running in safe
    environment
    Prevent
    introduction of
    PHP 7 code to
    PHP 5 boxes
    PHP 7 Deployment Plan
    Production
    Slow introduction
    to pools, careful
    eye on perf and
    errors
    @wcgallego
    

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25. 25
    PHPUnit

    Upgrade before you start!
    @wcgallego
    

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26. 26
    PHPUnit
    Tests: 17815
    Assertions: 61346
    Errors: 66
    Failures: 120
    https://github.com/krakjoe/uopz
    @wcgallego
    

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27. 27
    Phan
    https://github.com/etsy/phan
    @wcgallego
    

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28. 28
    
    Tee-ing Requests
    @wcgallego
    

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29. 29
    https://github.com/buger/gor
    @wcgallego
    

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30. 30
    PHP @ Etsy Timeline
    @wcgallego
    Spring

    2015
    Summer

    2015
    Fall

    2015
    January

    2016
    February

    2016
    Summer

    2016
    Single web node running PHP 7
    

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31. 31
    PHP @ Etsy Timeline
    @wcgallego
    Spring

    2015
    Summer

    2015
    Fall

    2015
    January

    2016
    February

    2016
    Summer

    2016
    PHP 7 deployed to all web nodes
    NPOUITTJODFCFHJOOJOHFYUFOTJPOTQPSUJOH
    NPOUITJOUFHSBUJOHJOUP&UTZ
    NPOUITBGUFSSFMFBTF
    

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32. 32
    ))7.1)1
    @wcgallego
    

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33. 33
    
    Other Snowflakes
    @wcgallego
    

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34. 34
    PHP @ Etsy Timeline
    @wcgallego
    Spring

    2015
    Summer

    2015
    Fall

    2015
    January

    2016
    February

    2016
    Summer

    2016
    Deployed to Dev VMs
    PHP 7 everywhere!
    

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35. 35
    Perf wins!
    @wcgallego
    

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36. .FNPSZXJOT
    36
    @wcgallego
    

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37. 4ZTUFN$16XJOT
    37
    @wcgallego
    

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38. 6TFS$16XJOT
    38
    @wcgallego
    

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39. )PNFQBHFEFMJWFSZXJOT
    39
    @wcgallego
    

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40. -JTUJOHEFMJWFSZXJOT
    40
    @wcgallego
    

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41. 'FXFSIPTUT
    41
    @wcgallego
    

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42. 42
    
    $BVUJPO
    @wcgallego
    

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43. $PEFQJUGBMMT6OJGPSN7BS1BSTJOH
    43
    @wcgallego
    $class->$foo['bar']();
    In PHP 5 that is interpreted as:
    $class->($foo['bar'])()
    while in PHP 7 it is:
    ($class->$foo)['bar']()
    It is easy enough to fix by adding curlies:
    $class->{$foo[‘bar']}()
    

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44. $PEFQJUGBMMT6OJGPSN7BS1BSTJOH
    44
    @wcgallego
    $class->$foo['bar']();
    In PHP 5 that is interpreted as:
    $class->($foo['bar'])()
    while in PHP 7 it is:
    ($class->$foo)['bar']()
    It is easy enough to fix by adding curlies:
    $class->{$foo[‘bar']}()
    

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45. $PEFQJUGBMMT6OJGPSN7BS1BSTJOH
    45
    @wcgallego
    $class->$foo['bar']();
    In PHP 5 that is interpreted as:
    $class->($foo['bar'])()
    while in PHP 7 it is:
    ($class->$foo)['bar']()
    It is easy enough to fix by adding curlies:
    $class->{$foo[‘bar']}()
    

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46. $PEFQJUGBMMT6OJGPSN7BS1BSTJOH
    46
    @wcgallego
    $class->$foo['bar']();
    In PHP 5 that is interpreted as:
    $class->($foo['bar'])()
    while in PHP 7 it is:
    ($class->$foo)['bar']()
    It is easy enough to fix by adding curlies:
    $class->{$foo[‘bar']}()
    

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47. $PEFQJUGBMMT"TTPDJBUJWF"SSBZ4PSUJOH
    $foo = [
    "a" => 1,
    "b" => 1
    ];
    asort($foo);
    print_r($foo);
    47
    @wcgallego
    PHP 5:
    Array
    (
    [b] => 1
    [a] => 1
    )
    PHP 7:
    Array
    (
    [a] => 1
    [b] => 1
    )
    

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48. $PEFQJUGBMMT"TTPDJBUJWF"SSBZ4PSUJOH
    $foo = [
    "a" => 1,
    "b" => 1
    ];
    asort($foo);
    print_r($foo);
    48
    @wcgallego
    PHP 5:
    Array
    (
    [b] => 1
    [a] => 1
    )
    PHP 7:
    Array
    (
    [a] => 1
    [b] => 1
    )
    

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49. $PEFQJUGBMMT"TTPDJBUJWF"SSBZ4PSUJOH
    $foo = [
    "a" => 1,
    "b" => 1
    ];
    asort($foo);
    print_r($foo);
    49
    @wcgallego
    PHP 5:
    Array
    (
    [b] => 1
    [a] => 1
    )
    PHP 7:
    Array
    (
    [a] => 1
    [b] => 1
    )
    

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50. $PEFQJUGBMMT$BUDIBCMF&SSPST
    50
    @wcgallego
    // PHP 5 era code that will break.
    function handler(Exception $e) { ... }
    set_exception_handler('handler');
    // PHP 5 and 7 compatible.
    function handler($e) { ... }
    // PHP 7 only.
    function handler(Throwable $e) { ... }
    

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51. $PEFQJUGBMMT3FNPWFE%FQSFDBUFE'VODUJPOT
    51
    @wcgallego
    mysql_* -> mysqli_*
    For example:

    mysql_connect() should now be
    mysqli_connect() or used PDO class
    Legacy extension: https://github.com/php/pecl-database-mysql
    

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52. 52
    0UIFSJODPNQBUJCMFDIBOHFT
    http://php.net/manual/en/migration70.incompatible.php
    http://php.net/manual/en/migration70.deprecated.php
    @wcgallego
    

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53. 53
    &YUFOTJPOT
    @wcgallego
    • gearman
    • msgpack
    • oauth
    • memcached
    • gmagick
    •…a dozen more!
    

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54. 54
    SOAP ’n Certs
    PHP 7 is stricter about cert comparisons
    @wcgallego
    

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55. 55
    SOAP ’n Certs
    1. Disable WSDL cache

    (http://lornajane.net/posts/2015/soapfault-when-switching-php-versions)
    2. Update your certs!
    3. use FQDN instead of IPs
    4.* Could also turn off peer verification (but probably not advisable)
    @wcgallego
    

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56. 56
    /6."
    @wcgallego
    

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57. 57
    On NUMA
    @wcgallego
    

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58. 58
    But enough of the doom and gloom...
    @wcgallego
    

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59. /FXGFBUVSFTUPDIFDLPVU
    • Scalar Type Declarations
    • Return Type Declarations
    • NULL coalescing operator
    • phpdbg
    • spaceship operator
    • const arrays
    59
    @wcgallego
    

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60. 60
    .PSFGFBUVSFT
    http://php.net/manual/en/migration70.new-features.php
    @wcgallego
    

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61. 'VUVSFUXFBLTBU&UTZ
    • File backed opcache - cli speed up, avoid
    thundering herd on graceful restarts
    • Better compilation! Latest GCC, ICC, etc.
    • FDO (Feedback Directed Optimization) as
    part of GCC > 5
    • Tuning to avoid filling up opcache as often
    61
    @wcgallego
    

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62. 1BSUJOHUIPVHIUT
    • Plan first, be ready to be flexible
    • Static analyzers/Tests/Teeing are wonderful
    • Have a back up plan
    • Don’t be afraid to contribute back to PHP
    • Get ready for a huge bucket of win
    62
    @wcgallego
    

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63. 63
    5IBOLT
    @wcgallego
    https://joind.in/talk/41de3
    

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64. 64
    <>IUUQTXXXGMJDLSDPNQIPUPTECSFLLF
    <>JNBHFIUUQXXXCVTJOFTTJOTJEFSDPNJOTJEFFUTZTOFXQFSLGJMMFEPGGJDF
    <>IUUQTXXXGMJDLSDPNQIPUPTKBOJUPST
    <>IUUQTXXXGMJDLSDPNQIPUPT!/
    <>IUUQTFOXJLJQFEJBPSHXJLJ1FSM
    <>IUUQTXXXGMJDLSDPNQIPUPTDPOCPO
    <>IUUQTXXXGMJDLSDPNQIPUPT!/
    <>IUUQTXXXGMJDLSDPNQIPUPT!/
    <>IUUQTXXXGMJDLSDPNQIPUPTFDPMJ
    @wcgallego
    

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