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<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Deploying PHP 7</title>
<meta name="description" content="Deploying PHP 7">
<meta name="author" content="Rasmus Lerdorf">
<meta name="apple-mobile-web-app-capable" content="yes" />
<meta name="apple-mobile-web-app-status-bar-style" content="black-translucent" />
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no, minimal-ui">
<link rel="stylesheet" href="/reveal.js/css/reveal.css">
<link rel="stylesheet" href="/reveal.js/css/theme/white.css" id="theme">
<!-- For syntax highlighting - note that these are not the generic highlight.js theme files - see https://github.com/nwinkler/reveal-highlight-themes -->
<link rel="stylesheet" href="/styles/xcode.css">
<!-- Override a few styles -->
<style>
/*
Not actually sure why this block isn't being picked up from the syntax highlight css
If you change the syntax highlight theme, copy the first block here
*/
.reveal pre {
width: 100%;
}
.reveal pre code {
display: block;
max-height: 600px;
overflow-x: auto;
padding: 0.5em;
line-height: 125%;
background: #fff;
color: black;
-webkit-text-size-adjust: none;
}
.reveal section img {
box-shadow: none;
border: none;
}
.reveal code.shell {
display: block;
overflow-x: auto;
padding: 0.5em;
background: #000;
color: #ddd;
line-height: 125%;
-webkit-text-size-adjust: none;
}
/* Left-align h3 and h4 if they are p elements */
h3.p {
text-align: left;
}
h4.p {
text-align: left;
}
/* and left-aligned but slightly indented bullet lists */
.reveal ul {
display: block;
margin: 0 0 1em 3em;
}
/* Example titles */
p.example {
text-align: left;
margin: 0 0 -0.5em 1em;
font-weight: bold;
}
/* Example output style */
pre.output {
display: block;
overflow-x: auto;
padding: 0.5em;
background: #ddd;
color: black;
line-height: 200%;
-webkit-text-size-adjust: none;
}
</style>
<!-- Printing and PDF exports -->
<script>
var link = document.createElement( 'link' );
link.rel = 'stylesheet';
link.type = 'text/css';
link.href = window.location.search.match( /print-pdf/gi ) ? '/reveal.js/css/print/pdf.css' : '/reveal.js/css/print/paper.css';
document.getElementsByTagName( 'head' )[0].appendChild( link );
</script>
<!-- Needed for charts to work. Fall back to network if no local copy -->
<script type='text/javascript' src='/jquery.min.js'></script>
<script>window.jQuery || document.write('<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js">\x3C/script>')</script>
<script src="/highcharts.js"></script>
<script>window.Highcharts || document.write('<script src="http://code.highcharts.com/highcharts.js">\x3C/script>')</script>
<!--[if lt IE 9]>
<script src="/reveal.js/lib/js/html5shiv.js"></script>
<![endif]-->
</head>
<body>
<div class="reveal">
<!-- Any section element inside of this container is displayed as a slide -->
<div class="slides">
<section>
<h1>Deploying PHP 7</h1>
<h3>PHPCONMX</h3>
<h3>Mexico City</h3>
<h3>Sept.23, 2016</h3>
<a href="http://talks.php.net/conmx">http://talks.php.net/conmx</a><br><br>
<p>Rasmus Lerdorf<br>
<small><a href="http://twitter.com/@rasmus">@rasmus</a></small>
</p>
<aside class="notes">
Notice: Undefined variable: notes in /home/rasmus/src/web/pres2/reveal_template.php on line 125
</aside>
</section>
<section>
<section id="php7_speed">
<img src="/presentations/slides/intro/php7trans-200.png" width="" height="">
<p class="p" style="font-size:1.1em;text-align:left;">✔ engine improvements</p>
<ul>
<li style="font-size: 1em;">100%+ performance gain on most real-world applications</li>
<li style="font-size: 1em;">Lower memory usage, sometimes drastically lower</li>
</ul>
</section> </section>
<section>
<section id="php7perfdetail">
<h1 style="text-align:center;">JIT?</h1>
</section>
<section id="php7perfdetail1">
<p class="p" style="font-size:1.1em;">Improve CPU cache usage</p>
<ul>
<li style="font-size: 1em;list-style-type: none;">Step 1: Decrease overall data</li>
<li style="font-size: 1em;list-style-type: none;">Step 2: Better data locality and less indirections</li>
<li style="font-size: 1em;list-style-type: none;">Step 3: Save the world!</li>
</ul>
</section>
<section id="php7perfdetail1">
<ul>
<li style="font-size: 1em;list-style-type: none;">zval size reduced from 24 to 16 bytes</li>
<li style="font-size: 1em;list-style-type: none;">Hashtable size reduced from 72 to 56 bytes</li>
<li style="font-size: 1em;list-style-type: none;">Hashtable bucket size reduced from 72 to 32 bytes</li>
<li style="font-size: 1em;list-style-type: none;">Immutable array optimization</li>
</ul>
<pre><code data-trim style="font-size:1.1em;">$a = [];
for($i=0; $i < 100000;$i++) {
$a[] = ['abc','def','ghi','jkl','mno','pqr'];
}
echo memory_get_usage(true);
// PHP 5.x 109M
// PHP 7.0 42M no opcache
// PHP 7.0 6M with opcache enabled</code></pre>
</section>
<section id="php7perfdetail2">
<ul>
<li style="font-size: 1em;list-style-type: none;">New memory allocator similar to jemalloc</li>
<li style="font-size: 1em;list-style-type: none;">Faster hashtable iteration API</li>
<li style="font-size: 1em;list-style-type: none;">Array duplication optimization</li>
<li style="font-size: 1em;list-style-type: none;">PCRE JIT enabled by default</li>
<li style="font-size: 1em;list-style-type: none;">Precomputed string hashes</li>
<li style="font-size: 1em;list-style-type: none;">Fast ZPP (ZendParseParameters) implementation</li>
<li style="font-size: 1em;list-style-type: none;">Faster stack-allocated zvals (instead of heap)</li>
<li style="font-size: 1em;list-style-type: none;">Optimized VM calling</li>
<li style="font-size: 1em;list-style-type: none;">Global register variables with gcc 4.8+</li>
<li style="font-size: 1em;list-style-type: none;">plus hundreds of micro-optimizations</li>
</ul>
</section>
<section id="php7detail4">
<h1 style="text-align:center;">JIT?</h1>
</section> </section>
<section>
<section id="drupalbench">
<div id="drupalbench_container" class="stretch" style="margin: 0 auto"></div>
<script src="presentations/slides/intro/nov3/drupalbench.js"></script>
</section> </section>
<section>
<section id="wpbench">
<div id="wpbench_container" class="stretch" style="margin: 0 auto"></div>
<script src="presentations/slides/intro/nov3/wpbench.js"></script>
</section>
<section id="fdo">
<p class="p" style="font-size:1.1em;text-align:center;">GCC Feedback-Directed Optimization (FDO)</p>
<pre><code class="shell nohighlight" data-trim style="font-size:1em;">$ make clean
$ make -j8 prof-gen
...
$ sapi/cgi/php-cgi -T 1000 /var/www/wordpress/index.php > /dev/null
$ make prof-clean
$ make -j8 prof-use</code></pre>
</section>
<section id="wpbench_fdo">
<div id="wpbench_fdo_container" class="stretch" style="margin: 0 auto"></div>
<script src="presentations/slides/intro/nov3/wpbench_fdo.js"></script>
</section> </section>
<section>
<section id="moodlebench">
<div id="moodlebench_container" class="stretch" style="margin: 0 auto"></div>
<script src="presentations/slides/intro/nov3/moodlebench.js"></script>
</section> </section>
<section>
<section id="wardrobebench">
<div id="wardrobebench_container" class="stretch" style="margin: 0 auto"></div>
<script src="presentations/slides/intro/nov3/wardrobebench.js"></script>
</section> </section>
<section>
<section id="cachetbench">
<div id="cachetbench_container" class="stretch" style="margin: 0 auto"></div>
<script src="presentations/slides/intro/nov3/cachetbench.js"></script>
</section> </section>
<section>
<section id="smembase">
<div id="smembase_container" class="stretch" style="margin: 0 auto"></div>
<script src="presentations/slides/intro/smembase.js"></script>
</section> </section>
<section>
<section id="smemdrupal">
<div id="smemdrupal_container" class="stretch" style="margin: 0 auto"></div>
<script src="presentations/slides/intro/smemdrupal.js"></script>
</section> </section>
<section>
<section id="smemwp">
<div id="smemwp_container" class="stretch" style="margin: 0 auto"></div>
<script src="presentations/slides/intro/smemwp.js"></script>
</section> </section>
<section>
<section id="smemmoodle">
<div id="smemmoodle_container" class="stretch" style="margin: 0 auto"></div>
<script src="presentations/slides/intro/smemmoodle.js"></script>
</section> </section>
<section>
<section id="php7">
<img src="/presentations/slides/intro/php7trans-200.png" width="" height="">
<p class="p" style="font-size:1.1em;text-align:left;">✔ engine improvements</p>
<ul>
<li style="font-size: 1em;">100%+ performance gain on most real-world applications</li>
<li style="font-size: 1em;">Lower memory usage, sometimes drastically lower</li>
</ul>
</section>
<section id="php7excep">
<p class="p" style="font-size:1.1em;text-align:left;">✔ Exceptions on Fatals</p>
<pre><code data-trim style="font-size:1.1em;">function call_method($obj) {
$obj->method();
}
call_method(null);</code></pre>
<pre><code class="shell nohighlight" data-trim style="font-size:0.85em;">Fatal error: Uncaught Error: Call to a member function method() on null in file:2
Stack trace:
#0 file(4): call_method(NULL)
#1 {main}
thrown in file on line 2</code></pre>
<pre><code data-trim style="font-size:1.1em;">try {
call_method(null);
} catch (Error $e) {
echo "Caught Exception: {$e->getMessage()}\n";
}</code></pre>
<pre><code class="shell nohighlight" data-trim style="font-size:0.85em;">Caught Exception: Call to a member function method() on null</code></pre>
</section>
<section id="php7hier">
<p class="p" style="font-size:2em;text-align:center;">PHP 7 Exception Hierarchy</p>
<br/>
<ul>
<li style="font-size: 1.5em;list-style-type: none;"><font color="ab5c5c">Throwable</font></li>
<li style="font-size: 1.25em;margin-left: 2em;list-style-type: none;">➥ <font color="ab5c5c">Exception</font> implements Throwable</li>
<li style="font-size: 1.25em;margin-left: 2em;list-style-type: none;">➥ <font color="ab5c5c">Error</font> implements Throwable</li>
<li style="font-size: 1em;margin-left: 4em;list-style-type: none;">➥ <font color="ab5c5c">TypeError</font> extends Error</li>
<li style="font-size: 1em;margin-left: 4em;list-style-type: none;">➥ <font color="ab5c5c">ParseError</font> extends Error</li>
</ul>
</section>
<section id="php7ret">
<p class="p" style="font-size:1.1em;text-align:left;">✔ Return Types</p>
<pre><code data-trim style="font-size:1.1em;">function get_config(): array {
return 42;
}
get_config();</code></pre>
<pre><code class="shell nohighlight" data-trim style="font-size:0.9em;">Fatal error: Uncaught TypeError: Return value of get_config() must be
of the type array, integer returned in file:2
Stack trace:
#0 file(4): get_config()
#1 {main}
thrown in file on line 2</code></pre>
</section>
<section id="php7STH">
<p class="p" style="font-size:1.1em;text-align:left;">✔ Coercive Scalar Types</p>
<pre><code data-trim style="font-size:1.1em;">function logmsg(string $msg, int $level, float $severity) {
var_dump($msg); // string(1) "1"
var_dump($level); // int(2)
var_dump($severity); // float(3)
}
logmsg(1, "2.5 bananas", 3);</code></pre>
<pre><code class="shell nohighlight" data-trim style="font-size:0.9em;">Notice: A non well formed numeric value encountered in file on line 2</code></pre>
<p class="p" style="font-size:1.1em;text-align:left;">✔ Strict Scalar Types</p>
<pre><code data-trim style="font-size:1.1em;">declare(strict_types=1);
...
logmsg(1, "2.5", 3);</code></pre>
<pre><code class="shell nohighlight" data-trim style="font-size:0.9em;">Fatal error: Uncaught TypeError: Argument 1 passed to logmsg() must be of the
type string, integer given, called in file on line 7 and defined in file:3
Stack trace:
#0 file(7): logmsg(1, '2.5', 3)
#1 {main}
thrown in file on line 2</code></pre>
</section>
<section id="php7anon">
<p class="p" style="font-size:1.1em;text-align:left;">✔ Anonymous Classes</p>
<pre><code data-trim style="font-size:1.2em;">return new class($controller) implements Page {
public function __construct($controller) {
/* ... */
}
/* ... */
};
class MyObject extends MyStuff {
public function getInterface() {
return new class implements MyInterface {
/* ... */
};
}
}</code></pre>
</section>
<section id="php7coalesce">
<p class="p" style="font-size:1.1em;text-align:left;">✔ Coalesce Operator</p>
<pre><code data-trim style="font-size:1.5em;">$a = NULL;
$b = 0;
$c = 2;
echo $a ?? $b; // 0
echo $c ?? $b; // 2
echo $a ?? $b ?? $c; // 0
echo $a ?? $x ?? $c; // 2</code></pre>
</section>
<section id="Spaceship">
<p class="p" style="font-size:1.1em;text-align:left;">✔ Spaceship Operator</p>
<img src="/presentations/slides/intro/lego-php-astronaut.png" width="230" height="345">
<pre><code data-trim style="font-size:1.1em;">function cmp_php5($a, $b) {
return ($a < $b) ? -1 : (($a >$b) ? 1 : 0);
}
function cmp_php7($a, $b) {
return $a <=> $b;
}</code></pre>
</section>
<section id="php7cleanups">
<p class="p" style="font-size:1.1em;text-align:left;">✔ Removal of many deprecated features<BR/>
(Your PHP4 code will break!)</p>
<pre><code data-trim>- ext/ereg (use ext/pcre instead)
- preg_replace() eval modifier (use preg_replace_callback() instead)
- ext/mysql (use ext/mysqli or ext/pdo_mysql instead)
- Assignment of new by reference
- Scoped calls of non-static methods from incompatible $this context
- dl() in php-fpm
- set_magic_quotes_runtime() and magic_quotes_runtime()
- set_socket_blocking() (use stream_set_blocking() instead)
- mcrypt_generic_end() (use mcrypt_generic_deinit() instead)
- mcrypt_ecb, mcrypt_cbc, mcrypt_cfb and mcrypt_ofb
(use mcrypt_encrypt() and mcrypt_decrypt() instead)
- datefmt_set_timezone_id() and IntlDateFormatter::setTimeZoneID()
(use datefmt_set_timezone() or IntlDateFormatter::setTimeZone() instead)
- xsl.security_prefs (use XsltProcessor::setSecurityPrefs() instead)
- iconv.input_encoding, iconv.output_encoding, iconv.internal_encoding,
mbstring.http_input, mbstring.http_output and mbstring.internal_encoding
(use php.input_encoding, php.internal_encoding and php.output_encoding instead)
- $is_dst parameter of the mktime() and gmmktime() functions
- # style comments in ini files (use ; style comments instead)
- String category names in setlocale() (use LC_* constants instead)
- Unsafe curl file uploads (use CurlFile instead)
- PDO::PGSQL_ATTR_DISABLE_NATIVE_PREPARED_STATEMENT driver option
(use PDO::ATTR_EMULATE_PREPARES instead)
- CN_match and SNI_server_name stream context option (use peer_name instead)</code></pre>
</section>
<section id="php7reserved">
<p class="p" style="font-size:1.1em;text-align:left;">✔ New reserved words:</p>
<ul>
<li style="font-size: 1em;list-style-type: none;">bool</li>
<li style="font-size: 1em;list-style-type: none;">int</li>
<li style="font-size: 1em;list-style-type: none;">float</li>
<li style="font-size: 1em;list-style-type: none;">string</li>
<li style="font-size: 1em;list-style-type: none;">null</li>
<li style="font-size: 1em;list-style-type: none;">false</li>
<li style="font-size: 1em;list-style-type: none;">true</li>
<li style="font-size: 1em;list-style-type: none;">resource</li>
<li style="font-size: 1em;list-style-type: none;">object</li>
<li style="font-size: 1em;list-style-type: none;">mixed</li>
<li style="font-size: 1em;list-style-type: none;">numeric</li>
</ul>
</section>
<section id="php7num">
<p class="p" style="font-size:1.1em;text-align:left;">✔ 64-bit integer support on Windows</p>
<p class="p" style="font-size:1.1em;text-align:left;">✔ Cleanup edge-case integer overflow/underflow</p>
<p class="p" style="font-size:1.1em;text-align:left;">✔ Support for strings with length >= 2^31 bytes in 64 bit builds.</p>
<p class="p" style="font-size:1.1em;text-align:left;">✔ Parse error on invalid numeric literals</p>
<pre><code data-trim>$mask = 0855; // Parse error: Invalid numeric literal</code></pre>
</section>
<section id="php7UVS">
<p class="p" style="font-size:1.1em;text-align:left;">✔ Uniform variable syntax</p>
<pre><code data-trim>// left-to-right
$this->$belongs_to['column']
// vs.
$this->{$belongs_to['column']}
// support missing combinations of operations
$foo()['bar']()
[$obj1, $obj2][0]->prop
getStr(){0}
// support nested ::
$foo['bar']::$baz
$foo::$bar::$baz
$foo->bar()::baz()
// support nested ()
foo()()
$foo->bar()()
Foo::bar()()
$foo()()
// support operations on arbitrary (...) expressions
(...)['foo']
(...)->foo
(...)->foo()
(...)::$foo
(...)::foo()
(...)()
// two more practical examples for the last point
(function() { ... })()
($obj->closure)()
// support all operations on dereferencable scalars
// (not very useful)
"string"->toLower()
[$obj, 'method']()
'Foo'::$bar</code></pre>
</section>
<section id="php7unicode">
<p class="p" style="font-size:1.1em;text-align:left;">✔ Unicode Codepoint Escape Syntax</p>
<pre><code data-trim style="font-size:1.2em;">echo "\u{202E}Right-to-left text";
echo " \u{26BD}";</code></pre>
<pre class="output" style="font-size:1.2em;">Right-to-left text ⚽ </pre> <p class="p" style="font-size:1.1em;text-align:left;">✔ ICU IntlChar class added to intl extension</p>
</section>
<section id="php7csprng">
<p class="p" style="font-size:1.1em;text-align:left;">✔ CSPRNG</p>
<pre><code data-trim style="font-size:1.2em;">$int = random_int(-500, 500);
$bytes = random_bytes(10);
var_dump( $int );
var_dump( bin2hex($bytes) );</code></pre>
<pre class="output" style="font-size:1.2em;">int(-31)
string(20) "b783d82da521b87c1c6c"
</pre> </section> </section>
<section>
<section id="bc7">
<h1 style="text-align:center;">Top-5 Things that might bite you</h1>
<br/>
<br/>
<br/>
<p class="p" style="font-size:1.5em;text-align:center;">For the full list see</p>
<div align="center" style="font-size: 1.25em; color: ; text-align: center; margin-left: ; margin-right: ; margin-top: -0.75em; margin-bottom: ;"><a href="http://php.net/manual/en/migration70.php" target="">php.net/migration70</a></div>
</section>
<section id="bc7_1">
<p class="p" style="font-size:1.1em;text-align:left;">Left-to-right semantics for complicated expressions</p>
<pre><code class="php" data-trim style="font-size:1.1em;">$$foo['bar']['baz'] // interpreted as ($$foo)['bar']['baz']
$foo->$bar['baz'] // interpreted as ($foo->$bar)['baz']
$foo->$bar['baz']() // interpreted as ($foo->$bar)['baz']()
Foo::$bar['baz']() // interpreted as (Foo::$bar)['baz']()</code></pre>
<p class="p" style="font-size:0.8em;text-align:left;">To restore the previous behaviour add explicit curly braces:</p>
<pre><code class="php" data-trim style="font-size:1.1em;">${$foo['bar']['baz']}
$foo->{$bar['baz']}
$foo->{$bar['baz']}()
Foo::{$bar['baz']}()</code></pre>
<p class="p" style="font-size:0.8em;text-align:left;">Detection: phan or unit test failures</p>
</section>
<section id="bc7_2">
<p class="p" style="font-size:1.1em;text-align:left;">Removed support for /e (PREG_REPLACE_EVAL) modifier</p>
<pre><code class="php" data-trim style="font-size:1.1em;">echo preg_replace('/:-:(.*?):-:/e', '$this->pres->\\1', $text);</code></pre>
<p class="p" style="font-size:0.8em;text-align:left;">Change to:</p>
<pre><code class="php" data-trim style="font-size:1.1em;">echo preg_replace_callback(
'/:-:(.*?):-:/',
function($matches) {
return $this->pres->{$matches[1]}; // Careful!
},
$text);</code></pre>
<p class="p" style="font-size:0.8em;text-align:left;">Detection: grep, warnings in logs or unit test failures</p>
</section>
<section id="bc7_3">
<p class="p" style="font-size:1.1em;text-align:left;">$HTTP_RAW_POST_DATA global removed</p>
<pre><code class="php" data-trim style="font-size:1em;">if (empty($GLOBALS['HTTP_RAW_POST_DATA']) &&
strpos($_SERVER['CONTENT_TYPE'], 'www-form-urlencoded') === false) {
$GLOBALS['HTTP_RAW_POST_DATA'] = file_get_contents("php://input");
}</code></pre>
<p class="p" style="font-size:0.8em;text-align:left;">Detection: grep, warnings in logs or unit test failures</p>
</section>
<section id="bc7_4">
<p class="p" style="font-size:1.1em;text-align:left;">session.lazy_write enabled by default</p>
<pre><code class="ini" data-trim style="font-size:1.1em;">session.lazy_write = 0</code></pre>
<p class="p" style="font-size:0.8em;text-align:left;">Detection: Can cause out-of-band session read timing issues</p>
</section>
<section id="bc7_5">
<p class="p" style="font-size:1.1em;text-align:left;">Invalid octal literals now produce a parse error</p>
<pre><code class="php" data-trim style="font-size:1.1em;">echo 05678; // PHP 5.x outputs 375</code></pre>
<pre class="output" style="font-size:0.5em;">Parse error: Invalid numeric literal in file.php on line 2 </pre> <p class="p" style="font-size:0.8em;text-align:left;">Detecting parse errors is easy: php -l</p>
</section> </section>
<section>
<section id="phan">
<h1 style="text-align:center;">Static Analysis</h1>
<br/>
<br/>
<br/>
<div align="center" style="font-size: 1.25em; color: ; text-align: center; margin-left: ; margin-right: ; margin-top: ; margin-bottom: ;"><a href="https://github.com/etsy/phan" target="">github.com/etsy/phan</a></div>
</section>
<section id="phan1">
<pre><code class="shell nohighlight" data-trim style="font-size:1em;">% phan -h
Usage: ./phan [options] [files...]
-f, --file-list <filename>
A file containing a list of PHP files to be analyzed
-r, --file-list-only
A file containing a list of PHP files to be analyzed to the
exclusion of any other directories or files passed in. This
is useful when running Phan from a stored state file and
passing in a small subset of files to be re-analyzed.
-l, --directory <directory>
A directory to recursively read PHP files from to analyze
-3, --exclude-directory-list <dir_list>
A comma-separated list of directories for which any files
included from that directory will not be analysis. Note
that adding a directory here will not cause its files to
be parsed.
-d, --project-root-directory
Hunt for a directory named .phan in the current or parent
directory and read configuration file config.php from that
path.
-m <mode>, --output-mode
Output mode from 'text', 'json', 'codeclimate', or 'checkstyle'
-o, --output <filename>
Output filename
-p, --progress-bar
Show progress bar
-a, --dump-ast
Emit an AST for each file rather than analyze
-e, --expand-file-list
Expand the list of files passed in to include any files
that depend on elements defined in those files. This is
useful when running Phan from a state file and passing in
just the set of changed files.
-q, --quick
Quick mode - doesn't recurse into all function calls
-b, --backward-compatibility-checks
Check for potential PHP 5 -> PHP 7 BC issues
-i, --ignore-undeclared
Ignore undeclared functions and classes
-y, --minimum-severity <level in {0,5,10}>
Minimum severity level (low=0, normal=5, critical=10) to report.
Defaults to 0.
-c, --parent-constructor-required
Comma-separated list of classes that require
parent::__construct() to be called
-x, --dead-code-detection
Emit issues for classes, methods, functions, constants and
properties that are probably never referenced and can
possibly be removed.
-j, --processes <int>
The number of parallel processes to run during the analysis
phase. Defaults to 1.
-z, --signature-compatibility
Analyze signatures for methods that are overrides to ensure
compatiiblity with what they're overriding.
-h,--help
This help information</code></pre>
</section>
<section id="phan2">
<pre><code class="shell nohighlight" data-trim style="font-size:1em;">% phan -i -b display.php
display.php:416 CompatError expression may not be PHP 7 compatible</code></pre>
<pre><code data-trim style="font-size:1em;">echo preg_replace('/:-:(.*?):-:/e', '$this->pres->\\1', $text);</code></pre>
<pre><code data-trim style="font-size:1em;">echo preg_replace_callback(
'/:-:(.*?):-:/',
function($matches) {
return $this->pres->$matches[1]; // Oops!
},
$text);</code></pre>
<pre><code data-trim style="font-size:1em;">echo preg_replace_callback(
'/:-:(.*?):-:/',
function($matches) {
return $this->pres->{$matches[1]}; // Ok
},
$text);</code></pre>
</section>
<section id="phan3">
<pre><code class="shell nohighlight" data-trim style="font-size:1em;">% git clone https://github.com/Seldaek/monolog.git
% cd monolog
% find . -name '*.php' | grep -v test > filelist.txt
% phan -i -f filelist.txt
./src/Monolog/Handler/ChromePHPHandler.php:178 PhanTypeMismatchReturn Returning type int but headersAccepted() is declared to return bool
./src/Monolog/Handler/ElasticSearchHandler.php:124 PhanTypeMismatchArgumentInternal Argument 3 (previous) is \elastica\exception\exceptioninterface but \runtimeexception::__construct() takes \runtimeexception|\throwable
./src/Monolog/Handler/FirePHPHandler.php:81 PhanTypeMismatchReturn Returning type array but createRecordHeader() is declared to return string
./src/Monolog/Handler/FirePHPHandler.php:153 PhanTypeMismatchArgumentInternal Argument 1 (array_arg) is string but \current() takes array
./src/Monolog/Handler/FirePHPHandler.php:154 PhanTypeMismatchArgumentInternal Argument 1 (array_arg) is string but \current() takes array
./src/Monolog/Handler/FirePHPHandler.php:154 PhanTypeMismatchArgumentInternal Argument 1 (array_arg) is string but \key() takes array
./src/Monolog/Handler/FlowdockHandler.php:70 PhanTypeMissingReturn Method \monolog\handler\flowdockhandler::getdefaultformatter is declared to return \monolog\formatter\formatterinterface but has no return value
./src/Monolog/Handler/GelfHandler.php:55 PhanTypeMismatchProperty Assigning null to property but \monolog\handler\gelfhandler::publisher is \gelf\imessagepublisher|\gelf\publisher|\gelf\publisherinterface
./src/Monolog/Handler/MandrillHandler.php:49 PhanSignatureMismatch Declaration of function send($content, array $records) should be compatible with function send(string $content, array $records) defined in ./src/Monolog/Handler/MailHandler.php:46
./src/Monolog/Handler/NativeMailerHandler.php:117 PhanSignatureMismatch Declaration of function send($content, array $records) should be compatible with function send(string $content, array $records) defined in ./src/Monolog/Handler/MailHandler.php:46
./src/Monolog/Handler/RedisHandler.php:41 PhanTypeMismatchDefault Default value for int $capSize can't be bool
./src/Monolog/Handler/SocketHandler.php:115 PhanTypeMismatchProperty Assigning float to property but \monolog\handler\sockethandler::timeout is int
./src/Monolog/Handler/SocketHandler.php:126 PhanTypeMismatchProperty Assigning float to property but \monolog\handler\sockethandler::writingTimeout is int
./src/Monolog/Handler/SocketHandler.php:218 PhanTypeMismatchArgumentInternal Argument 2 (seconds) is float but \stream_set_timeout() takes int
./src/Monolog/Handler/SocketHandler.php:218 PhanTypeMismatchArgumentInternal Argument 3 (microseconds) is float but \stream_set_timeout() takes int
./src/Monolog/Handler/SocketHandler.php:274 PhanTypeMismatchProperty Assigning resource to property but \monolog\handler\sockethandler::resource is null
./src/Monolog/Handler/StreamHandler.php:65 PhanTypeMismatchProperty Assigning null to property but \monolog\handler\streamhandler::stream is resource|string
./src/Monolog/Handler/StreamHandler.php:86 PhanTypeMismatchProperty Assigning null to property but \monolog\handler\streamhandler::stream is resource|string
./src/Monolog/Handler/StreamHandler.php:105 PhanTypeMismatchProperty Assigning array|string to property but \monolog\handler\streamhandler::errorMessage is null
./src/Monolog/Handler/SwiftMailerHandler.php:43 PhanSignatureMismatch Declaration of function send($content, array $records) should be compatible with function send(string $content, array $records) defined in ./src/Monolog/Handler/MailHandler.php:46
./src/Monolog/Handler/SyslogUdp/UdpSocket.php:38 PhanTypeMismatchProperty Assigning null to property but \monolog\handler\syslogudp\udpsocket::socket is resource</code></pre>
</section>
<section id="phan4">
<pre><code class="shell nohighlight" data-trim style="font-size:1em;">ChromePHPHandler.php:178 PhanTypeMismatchReturn Returning type int but headersAccepted() is declared to return bool</code></pre>
<pre><code class="php" data-trim style="font-size:1em;">/**
* Verifies if the headers are accepted by the current user agent
*
* @return Boolean
*/
protected function headersAccepted() {
if (empty($_SERVER['HTTP_USER_AGENT'])) {
return false;
}
return preg_match('{\bChrome/\d+[\.\d+]*\b}', $_SERVER['HTTP_USER_AGENT']);
}</code></pre>
<img src="/presentations/slides/intro/preg_match.png" align="center" width="1050" height="170">
</section>
<section id="phan5">
<pre><code class="shell nohighlight" data-trim style="font-size:1em;">FirePHPHandler.php:154 PhanTypeMismatchArgumentInternal Argument 1 (array_arg) is string but \current() takes array</code></pre>
<pre><code class="php" data-trim style="font-size:1em;">/**
* Base header creation function used by init headers & record headers
*
* @param array $meta Wildfire Plugin, Protocol & Structure Indexes
* @param string $message Log message
* @return array Complete header string ready for the client as key and message as value
*/
protected function createHeader(array $meta, $message) {
$header = sprintf('%s-%s', self::HEADER_PREFIX, join('-', $meta));
return array($header => $message);
}
/**
* Creates message header from record
*
* @see createHeader()
* @param array $record
* @return string
*/
protected function createRecordHeader(array $record)
{
// Wildfire is extensible to support multiple protocols & plugins in a single request,
// but we're not taking advantage of that (yet), so we're using "1" for simplicity's sake.
return $this->createHeader(
array(1, 1, 1, self::$messageIndex++),
$record['formatted']
);
}
/**
* Creates & sends header for a record, ensuring init headers have been sent prior
*
* @see sendHeader()
* @see sendInitHeaders()
* @param array $record
*/
protected function write(array $record)
{
if (!self::$sendHeaders) {
return;
}
// WildFire-specific headers must be sent prior to any messages
if (!self::$initialized) {
self::$initialized = true;
self::$sendHeaders = $this->headersAccepted();
if (!self::$sendHeaders) {
return;
}
foreach ($this->getInitHeaders() as $header => $content) {
$this->sendHeader($header, $content);
}
}
$header = $this->createRecordHeader($record);
if (trim(current($header)) !== '') {
$this->sendHeader(key($header), current($header));
}
}</code></pre>
</section> </section>
<section>
<section id="php7_tune_phpinfo">
<h2 margin-bottom="2em">PHP 7 Tuning</h2><br>
<p class="p" style="font-size:2em;">Check your phpinfo()</p>
<img src="/presentations/slides/intro/phpinfo1.png" width="714" height="94">
</section>
<section id="php7_tune_opcache">
<p class="p" style="font-size:2em;">Opcache</p>
<pre><code class="ini" data-trim style="font-size:1.1em;">opcache.memory_consumption=2048
opcache.max_accelerated_files=100000
opcache.validate_timestamps=1
opcache.revalidate_freq=2
opcache.save_comments=0
opcache.enable_file_override=0
opcache.enable_cli=0
opcache.max_wasted_percentage=10
opcache.interned_strings_buffer=128
opcache.fast_shutdown=1
opcache.huge_code_pages=1</code></pre>
</section>
<section id="php7_tune_opcache2">
<p class="p" style="font-size:2em;">Opcache</p>
<img src="/presentations/slides/intro/phpinfo2.png" width="710" height="418">
</section>
<section id="php7_tune_huge">
<p class="p" style="font-size:2em;">Huge Pages</p>
<pre><code class="shell nohighlight" data-trim style="font-size:1.2em;">$ sysctl -w vm.nr_hugepages=512
vm.nr_hugepages = 512
(Add it to your /etc/sysctl.conf)
$ grep Huge /proc/meminfo
AnonHugePages: 6144 kB
HugePages_Total: 512
HugePages_Free: 300
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB</code></pre>
<pre><code class="ini" data-trim style="font-size:1.1em;">USE_ZEND_ALLOC_HUGE_PAGES=1 httpd ...</code></pre>
</section>
<section id="php7_tune_realpath">
<p class="p" style="font-size:2em;">increase realpath_cache_size</p>
<pre><code class="ini" data-trim style="font-size:2em;">realpath_cache_size=128k</code></pre>
</section>
<section id="php7_tune_mysql">
<p class="p" style="font-size:2em;">If using MySQL, use mysqlnd</p>
<img src="/presentations/slides/intro/mysqli.png" align="center" width="958" height="167">
<img src="/presentations/slides/intro/pdo.png" align="center" width="952" height="95">
<p class="p" style="font-size:1em;">Check your command buffer usage</p>
<img src="/presentations/slides/intro/mysqlnd.png" align="center" width="947" height="140">
</section>
<section id="php7_tune_tmpfs">
<p class="p" style="font-size:2em;">DocumentRoot on tmpfs</p>
<pre><code class="shell nohighlight" data-trim style="font-size:1em;">$ mount | grep tmpfs
tmpfs on /var/www type tmpfs (rw,relatime,size=12288000k,mode=755)
$ ls -la /var/www
total 5
drwxr-xr-x 5 root root 160 Feb 23 02:47 .
drwxr-xr-x 26 root root 4096 Feb 7 19:40 ..
lrwxrwxrwx 1 root root 14 Feb 23 02:47 current -> /var/www/A
drwxrwxr-x 25 apache apache 640 Feb 11 22:04 A
drwxrwxr-x 25 apache apache 640 Feb 11 22:04 B</code></pre>
</section>
<section id="php7_tune_app">
<p class="p" style="font-size:2em;">Application-level changes?</p>
<p class="example">Remember this?</p>
<pre><code data-trim style="font-size:1.1em;">$a = [];
for($i=0; $i < 100000;$i++) {
$a[] = ['abc','def','ghi','jkl','mno','pqr'];
}
echo memory_get_usage(true);
// PHP 5.x 109M
// PHP 7.0 42M no opcache
// PHP 7.0 6M with opcache enabled</code></pre>
<p class="example">Use it!</p>
<pre><code data-trim style="font-size:1.1em;">include 'config.php'; // $config = [ ... ]</code></pre>
<pre><code data-trim style="font-size:1.1em;">include 'countries.php'; // $countries = [ 'CA'=>'Canada', ... ]</code></pre>
</section> </section>
<section>
<section id="numa">
<h2 margin-bottom="2em">Hyperthreading and NUMA</h2><br>
<ul>
<li style="font-size: 1em;list-style-type: circle;">HyperThreading handles extreme loads better</li>
<li style="font-size: 1em;list-style-type: circle;">If you don't have multi-socket servers, turn on HT and move on</li>
<li style="font-size: 1em;list-style-type: circle;">For multi-socket servers, things get interesting</li>
</ul>
</section>
<section id="numa_singlesocket">
<p class="example">Digital Ocean</p>
<pre><code class="shell nohighlight" data-trim style="font-size:1em;">$ lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 2
On-line CPU(s) list: 0,1
Thread(s) per core: 1
Core(s) per socket: 1
Socket(s): 2
NUMA node(s): 1
Vendor ID: GenuineIntel
CPU family: 6
Model: 63
Model name: Intel(R) Xeon(R) CPU E5-2650L v3 @ 1.80GHz
Stepping: 2
CPU MHz: 1797.917
BogoMIPS: 3595.83
Virtualization: VT-x
Hypervisor vendor: KVM
Virtualization type: full
L1d cache: 32K
L1i cache: 32K
L2 cache: 256K
L3 cache: 30720K
NUMA node0 CPU(s): 0,1</code></pre>
</section>
<section id="numa_multisocket">
<p class="example">Multi-socket bare metal without HT</p>
<pre><code class="shell nohighlight" data-trim style="font-size:1em;">$ lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 24
On-line CPU(s) list: 0-23
Thread(s) per core: 1
Core(s) per socket: 12
Socket(s): 2
NUMA node(s): 2
Vendor ID: GenuineIntel
CPU family: 6
Model: 63
Model name: Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz
Stepping: 2
CPU MHz: 1203.320
BogoMIPS: 5005.24
Virtualization: VT-x
L1d cache: 32K
L1i cache: 32K
L2 cache: 256K
L3 cache: 30720K
NUMA node0 CPU(s): 0-11
NUMA node1 CPU(s): 12-23</code></pre>
</section>
<section id="numa_multisocket_ht">
<p class="example">Multi-socket bare metal with HT</p>
<pre><code class="shell nohighlight" data-trim style="font-size:1em;">$ lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 48
On-line CPU(s) list: 0-47
Thread(s) per core: 2
Core(s) per socket: 12
Socket(s): 2
NUMA node(s): 2
Vendor ID: GenuineIntel
CPU family: 6
Model: 63
Model name: Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz
Stepping: 2
CPU MHz: 1200.000
BogoMIPS: 5004.73
Virtualization: VT-x
L1d cache: 32K
L1i cache: 32K
L2 cache: 256K
L3 cache: 30720K
NUMA node0 CPU(s): 0-11,24-35
NUMA node1 CPU(s): 12-23,36-47</code></pre>
</section>
<section id="htop_graphs">
<img src="/presentations/slides/intro/htop_ht.png" align="center" width="800" height="325">
<img src="/presentations/slides/intro/htop.png" align="center" width="979" height="229">
</section>
<section id="numa_graph">
<img src="/presentations/slides/intro/numa_ht.png" align="center" width="979" height="507">
</section>
<section id="numa_solutions">
<br/>
<h4 class="p">Solutions?</h4>
<ul>
<li style="font-size: 1em;list-style-type: circle;">numactl --interleave=all httpd/php-fpm</li>
<li style="font-size: 1em;list-style-type: circle;">split multi-socket with containers</li>
<li style="font-size: 1em;list-style-type: circle;">BIOS Snoop Mode setting? HS/ES/COD?</li>
<li style="font-size: 1em;list-style-type: circle;">ignore it</li>
</ul>
</section> </section>
<section>
<section id="deploy">
<h1 style="text-align:center;">Let's deploy it!</h1>
</section>
<section id="deploy0">
<p class="p" style="font-size:2em;text-align:left;">Atomic</p>
<p class="p" style="font-size:2em;text-align:left;">No performance hit</p>
<ul>
<li style="font-size: 1.5em;">No restarts</li>
<li style="font-size: 1.5em;">No LB removal</li>
<li style="font-size: 1.5em;">No thundering herd</li>
<li style="font-size: 1.5em;">Cache reuse</li>
</ul>
</section>
<section id="deploy1">
<p class="p" style="font-size:1.1em;text-align:left;">Must be able to serve two versions of the site concurrently!</p>
<img src="/presentations/slides/intro/atomic_deploy1.png" width="" height="">
</section>
<section id="deploy2">
<img src="/presentations/slides/intro/atomic_deploy2.png" width="" height="">
</section>
<section id="deploy3">
<p class="p" style="font-size:1.1em;text-align:left;">Requests that begin on DocumentRoot A must finish on A</p>
</section>
<section id="deploy4">
<p class="p" style="font-size:1.1em;text-align:left;">Set the DocumentRoot to symlink target!</p>
<p class="p" style="font-size:1.1em;text-align:left;">Easy with nginx</p>
<pre><code class="ini" data-trim style="font-size:1.1em;">fastcgi_param DOCUMENT_ROOT $realpath_root</code></pre>
<p class="p" style="font-size:1.1em;text-align:left;">Apache</p>
<div align="left" style="font-size: 1.25em; color: ; text-align: left; margin-left: 1em; margin-right: ; margin-top: ; margin-bottom: ;"><a href="https://github.com/etsy/mod_realdoc" target="">github.com/etsy/mod_realdoc</a></div>
</section>
<section id="deploy5">
<p class="p" style="font-size:1.1em;text-align:left;">Avoid hardcoding full paths</p>
<p class="p" style="font-size:1.1em;text-align:left;">Watch your include_path setting</p>
<p class="p" style="font-size:1.1em;text-align:left;">incpath extension can resolve your include_path for you</p>
<div align="left" style="font-size: 1.25em; color: ; text-align: left; margin-left: 1em; margin-right: ; margin-top: ; margin-bottom: ;"><a href="https://github.com/etsy/incpath" target="">https://github.com/etsy/incpath</a></div>
</section>
<section id="deploy6">
<p class="p" style="font-size:1.1em;text-align:left;">Version all static assets</p>
<p class="p" style="font-size:1.1em;text-align:left;">DB Schema changes need special care</p>
</section> </section>
<section>
<section id="prod_perc95">
<h2 margin-bottom="2em">PHP 7 in production</h2><br>
<img src="/presentations/slides/intro/perc95.png" align="center" width="882" height="465">
</section>
<section id="prod_cpu">
<img src="/presentations/slides/intro/cpu.png" align="center" width="882" height="465">
</section>
<section id="prod_mem">
<img src="/presentations/slides/intro/mem.png" align="center" width="882" height="465">
</section> </section>
<section>
<section id="thank_you">
<h2 style="text-align:center;">Thank You</h2>
<div align="left" style="font-size: 1.2em; color: ; text-align: left; margin-left: 2em; margin-right: ; margin-top: ; margin-bottom: ;"><a href="https://github.com/rlerdorf/php7dev" target="">https://github.com/rlerdorf/php7dev</a></div>
<div align="left" style="font-size: 1.2em; color: ; text-align: left; margin-left: 2em; margin-right: ; margin-top: ; margin-bottom: ;"><a href="https://github.com/rlerdorf/phan" target="">https://github.com/rlerdorf/phan</a></div>
<div align="left" style="font-size: 1.2em; color: ; text-align: left; margin-left: 2em; margin-right: ; margin-top: ; margin-bottom: ;"><a href="https://bugs.php.net" target="">https://bugs.php.net</a></div>
<div align="left" style="font-size: 1.2em; color: ; text-align: left; margin-left: 2em; margin-right: ; margin-top: ; margin-bottom: ;"><a href=":-:url:-:" target="">http://talks.php.net/conmx</a></div>
<br/>
<br/>
<br/>
<p class="p" style="font-size:1.1em;">Report Bugs</p>
<p class="p" style="font-size:1.1em;">Useful bug reports, please!</p>
</section> </section>
</div>
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