Scalability Issues ... cure first, prevent later

Slides for my PHPBenelux UG session in Houthalen on May 30th

Transcript

2. Evangelist
6. @ThijsFeryn
7. Please3 rate3my3talk3on3 Joind.in https://joind.in/6577
9. It3works3on3my3computer
11. It’s3the3internet’s3fault
12. Suits & hipsters
13. “Isn't'hos*ng' supposed'to'be'a' bulk'product?”
14. “The'Cloud'will' make'sure'my'app' scales”
15. “Large'campaigns' on'shared'hos*ng,' why'is'that'a' problem?”
16. “What's'a' database'index?”
17. “We'll'solve'that' with'an'Ajax'call”
18. “We'll'probably'have' 10.000'visitors'on' the'next'campaign”
19. GeBng3the3numbers3right
20. Let’s3do3a3complete3rewrite3!
21. Have3you3got3the3Gme?
22. Or3the3money?
23. What3do3you3do?
24. Nothing
25. Throw3 servers3at3 the3 problem
26. Do3some3 tricks3!
27. Throw3servers3at3the3problem
28. Scale3verGcally
29. Fast Cheap vs Limited Expensive Long% term Short% term
30. Scale3horizontally
31. Efficient Unlimited vs ConsideraGons IniGal3effort Long% term Short% term
32. What3kind3of3infrastructure3do3you3need?
33. What3kind3of3infrastructure3do3you3need? One3big3 box?
34. What3kind3of3infrastructure3do3you3need? Scale3across3 1003nodes?
35. What3kind3of3infrastructure3do3you3need? That3big3F53 loadbalancer?
36. What3kind3of3infrastructure3do3you3need? Only3the3DB3 gets3 hammered
37. What3kind3of3infrastructure3do3you3need? Lots3of3staGc3 traffic
38. What3kind3of3infrastructure3do3you3need? Shared3hosGng3 will3do3...3 except3during3the3 month3of3the3event
39. About3a3mulGYserver3setup
40. Goal:3(almost)3no3code3changes
41. Cache
42. Why?
43. Is3caching3 the3 answer?
44. Frontend Backend Data% cache Opcode% cache Page% cache APC Memcached SQLite File Redis +more +more
45. What? When3not? How3long? CompaGbility Limited3size
46. Tricks
47. RewriteEngine*On RewriteCond*%{REQUEST_FILENAME}*=s*[OR] RewriteCond*%{REQUEST_FILENAME}*=l*[OR] RewriteCond*%{REQUEST_FILENAME}*=d RewriteRule*^.*$*=*[NC,L] RewriteRule*^.*$*index.php*[NC,L] Use3mod_rewrite Hit3frontcontroller3if3resource3doesn’t3exist
48. Use3mod_rewrite Write3output3to3file3and3print3to3screen <?php require('db.php'); $data = db_get_content_from_uri( $_SERVER['REQUEST_URI']); $fp = fopen(dirname(__FILE__). $_SERVER['REQUEST_URI'], 'w'); fwrite($fp, $data); fclose($fp); echo $data;
49. APC
50. Auto3prepend3&3auto3append AutomaGcally3executed3before3every3request [PHP] auto_prepend_file*“/path/to/prepend.php” auto_append_file*“/path/to/append.php”
51. Auto3prepend Read3from3cache3or3start3output3buffer <?php if($_SERVER['REQUEST_METHOD'] == 'GET'){ $key = md5('http://'.$_SERVER['HTTP_HOST']. $_SERVER['REQUEST_URI']); if(($output = apc_fetch($key)) !== false){ echo $output; exit(); } ob_start(); }
52. Auto3append Close3output3buffer,3store3data3in3cache3&3 print3output <?php if($_SERVER['REQUEST_METHOD'] == 'GET'){ $output = ob_get_contents(); ob_end_clean(); $key = md5('http://'.$_SERVER['HTTP_HOST']. $_SERVER['REQUEST_URI']); apc_store($key,$output,20); echo $output; }
53. Data3cache Caching3layer3 before3on3top3 of3the3 database
54. <?php class Data { private $_mysqlDependency; public function __construct($mysqlDependency) { $this->_mysqlDependency = $mysqlDependency; } public function fetchQueryFromDatabase($key) { return $this->_mysqlDependency- >fetchQueryEscaped("SELECT * FROM `myTable` WHERE `myKey` = '%s'",$key); } } No% cache
55. <?php class Data { private $_namespace = 'myNamespace_'; private $_ttl = 3600; private $_mysqlDependency; public function __construct($mysqlDependency) { $this->_mysqlDependency = $mysqlDependency; } public function fetchQueryFromDatabase($key) { if(($value = apc_fetch(md5( $this->_namespace.$key))) === false){ $value = $this->_fetchDataFromDatabase($key); $this->_storeDataInCache($key,$value); } return $value; } ... Override% &%use%cache Read% from%DB%&% store%in%cache
56. ... private function _storeDataInCache($key,$value) { apc_store(md5($this->_namespace.$key),$value, $this->_ttl); return $this; } private function _fetchQueryFromDatabase($key) { return $this->_mysqlDependency- >fetchQueryEscaped("SELECT * FROM `myTable` WHERE `myKey` = '%s'",$key); } } Fetch% from%DB Store% in%cache
57. You3can3also3use3Memcached
58. You3can3also3use3Memcached memcached.sess_prefix = "memc.sess.key." session.save_path="127.0.0.1:11211" session.save_handler = memcached Also% for%session% handling
59. Reverse3 (caching)3 proxies
60. Put3‘em3before3 your3 webserver
61. They3honor3 your3caching3 headers
63. backend default { .host = "127.0.0.1"; .port = "8080"; } acl purge { "localhost"; "127.0.0.1"; "some.host.name.com"; "1.2.3.4"; }
64. sub vcl_recv { if (req.request == "PURGE") { if (!client.ip ~ purge) { error 405 "Not allowed: " + client.ip; } return(lookup); } if (req.request != "GET" && req.request != "HEAD" && req.request != "PUT" && req.request != "POST" && req.request != "TRACE" && req.request != "OPTIONS" && req.request != "DELETE") { return (pipe); }
65. if (req.request != "GET" && req.request != "HEAD") { return (pass); } if (req.http.Accept-Encoding) { if (req.url ~ "\.(gif|jpg|jpeg|swf|flv|mp3|mp4| pdf|ico|png|gz|tgz|bz2)(\?.*|)$") { remove req.http.Accept-Encoding; } else if (req.http.Accept-Encoding ~ "gzip") { set req.http.Accept-Encoding = "gzip"; } else if (req.http.Accept-Encoding ~ "deflate"){ set req.http.Accept-Encoding = "deflate"; } else { remove req.http.Accept-Encoding; } }
66. if (req.url ~ "\.(gif|jpg|jpeg|swf|css|js|flv|mp3| mp4|pdf|ico|png)(\?.*|)$") { unset req.http.cookie; set req.url = regsub(req.url, "\?.*$", ""); return (lookup); } if (req.url ~ "\?(utm_(campaign|medium|source|term)| adParams|client|cx|eid|fbid|feed|ref(id|src)?|v(er| iew))=") { set req.url = regsub(req.url, "\?.*$", ""); } if (req.http.cookie ~ "^ *$") { unset req.http.cookie; }
67. sub vcl_fetch { if (req.url ~ "wp-(login|admin)" || req.url ~ "preview=true" || req.url ~ "xmlrpc.php") { return (hit_for_pass); } if ( (!(req.url ~ "(wp-(login|admin)|login)"))) { unset beresp.http.set-cookie; set beresp.ttl = 1h; } if (req.url ~ "\.(gif|jpg|jpeg|swf|css|js|flv|mp3| mp4|pdf|ico|png)(\?.*|)$") { set beresp.ttl = 365d; } }
68. sub vcl_deliver { if (obj.hits > 0) { set resp.http.X-Cache = "HIT"; } else { set resp.http.X-Cache = "MISS"; } } sub vcl_hit { if (req.request == "PURGE") { purge; set obj.ttl = 0s; error 200 "OK"; } } sub vcl_miss { if (req.request == "PURGE") { purge; error 200 "OK"; } }
69. FPM hfp://www.php.net/manual/en/install.fpm.configuraGon.php
70. [www] listen = 9000 user = www-data group = www-data pm = dynamic pm.max_children = 10 pm.start_servers = 4 pm.max_spare_servers = 6 pm.max_requests = 500 php_admin_value[sendmail_path] = /usr/sbin/sendmail -t -i -f www@my.domain.com php_flag[display_errors] = off php_admin_value[error_log] = /var/log/fpm-php.www.log php_admin_flag[log_errors] = on php_admin_value[memory_limit] = 32M
72. upstream fpm { server php1.server.com:9000; server php2.server.com:9000; } upstream memcached { server memcached1.server.com:11211; server memcached2.server.com:11211; } server { root /var/www; index index.php index.html index.htm; server_name nginx.server.com; location / { try_files $uri $uri/ /index.php; } location @php { fastcgi_pass fpm; fastcgi_index index.php; include fastcgi_params; }
73. location ~ \.php$ { set $memcached_key $request_uri; memcached_pass memcached; memcached_next_upstream not_found; default_type text/html; error_page 404 405 502 = @php; } location ~* \.(?:ico|css|js|gif|jpe?g|png)$ { expires max; add_header Pragma public; add_header Cache-Control "public, must- revalidate, proxy-revalidate"; } }
74. location ~ \.php$ { set $memcached_key $request_uri; memcached_pass memcached; memcached_next_upstream not_found; default_type text/html; error_page 404 405 502 = @php; } location ~* \.(?:ico|css|js|gif|jpe?g|png)$ { expires max; add_header Pragma public; add_header Cache-Control "public, must- revalidate, proxy-revalidate"; } }
76. Content Delivery Network
77. +3 W33Total3 Cache
82. ✓Enable3caching ✓Enable3cron.php ✓Configure3log3retenGon ✓Flat3catalog ✓Enable3compilaGon ✓Install3Varnish3Cache3plugin ✓Split3frontend3&3backend3servers ✓Perform3indexing3on3separate3 server
83. <global> <cache> <backend>apc</backend> <prefix>MAGE_</prefix> </cache> </global>
84. <global> <cache> <backend>memcached</backend> <memcached> <servers> <server> <host><![CDATA[127.0.0.1]]></host> <port><![CDATA[11211]]></port> <persistent><![CDATA[1]]></persistent> </server> </servers> <compression><![CDATA[0]]></compression> <cache_dir><![CDATA[]]></cache_dir> <hashed_directory_level><![CDATA[]]></hashed_directory_level> <hashed_directory_umask><![CDATA[]]></hashed_directory_umask> <file_name_prefix><![CDATA[]]></file_name_prefix> </memcached> </cache> </global>
86. Boost Varnish Memcached
87. Other3tricks3...
88. Mess3with3the3hosts3file Test3load3&3change3docroot Play3with3Apache3&3MySQL3 seBngs Add3a3database3index Enable3MySQL3query3caching
89. Don’t3be3clueless
90. Ask3for3help
91. Apply3the3tricks
92. And3don’t3forget3to3refactor3alerwards
93. And3then3relax3...3and3be3happy