isucon4予選AMIが公開されたのでPHPでやってみた（score:54491）

index.php

<?php
require_once 'limonade/lib/limonade.php';

function configure() {
  option('base_uri', '/');
  option('session', 'isu4_qualifier_session');

  $host = getenv('ISU4_DB_HOST') ?: 'localhost';
  $port = getenv('ISU4_DB_PORT') ?: 3306;
  $dbname = getenv('ISU4_DB_NAME') ?: 'isu4_qualifier';
  $username = getenv('ISU4_DB_USER') ?: 'root';
  $password = getenv('ISU4_DB_PASSWORD');
  $db = null;
  try {
    $db = new PDO(
      'mysql:host=' . $host . ';port=' . $port. ';dbname=' . $dbname,
      $username,
      $password,
      [ PDO::ATTR_PERSISTENT => true,
        PDO::MYSQL_ATTR_INIT_COMMAND => 'SET CHARACTER SET `utf8`',
      ]
    );
  } catch (PDOException $e) {
    halt("Connection faild: $e");
  }
  $db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

  option('db_conn', $db);

  $config = [
    'user_lock_threshold' => getenv('ISU4_USER_LOCK_THRESHOLD') ?: 3,
    'ip_ban_threshold' => getenv('ISU4_IP_BAN_THRESHOLD') ?: 10
  ];
  option('config', $config);
}

function uri_for($path) {
  $host = $_SERVER['HTTP_X_FORWARDED_HOST'] ?: $_SERVER['HTTP_HOST'];
  return 'http://' . $host . $path;
}

function get($key) {
  return set($key);
}

function before() {
  layout('base.html.php');
}

function calculate_password_hash($password, $salt) {
  return hash('sha256', $password . ':' . $salt);
}

function login_log($succeeded, $login, $user_id=null, $ip=null, $created_at=null, $insert = true) {

  if (is_null($ip)) $ip = $_SERVER['REMOTE_ADDR'];
  if (is_null($created_at)) $created_at = date('Y-m-d H:i:s');
  $log = array('created_at' => $created_at, 'user_id' => $user_id, 'login' => $login, 'ip' => $ip, 'succeeded' => $succeeded);

  $db = option('db_conn');

  if ($insert) {
    $stmt = $db->prepare('INSERT DELAYED INTO login_log (`created_at`, `user_id`, `login`, `ip`, `succeeded`) VALUES (:created_at,:user_id,:login,:ip,:succeeded)');
    $stmt->bindValue(':created_at', $log['created_at']);
    $stmt->bindValue(':user_id', $log['user_id']);
    $stmt->bindValue(':login', $log['login']);
    $stmt->bindValue(':ip', $log['ip']);
    $stmt->bindValue(':succeeded', $log['succeeded']  ? 1 : 0);
    $stmt->execute();
  }

  $ip_key   = 'fail_ip_' . $ip;
  $user_key = 'fail_user_' . $user_id;
  if ($succeeded) {
    apc_store($ip_key, 0);
    if (!is_null($user_id)) {
      apc_store($user_key, 0);
      if (apc_exists("now_login_" . $user_id)) {
        apc_store("last_login_" . $user_id, apc_fetch("now_login_" . $user_id));
      }
      apc_store("now_login_" . $user_id, $log);
    }
  } else {
    if (apc_exists($ip_key)) {
      apc_inc($ip_key);
    } else {
      apc_store($ip_key, 1);
    }
    if (!is_null($user_id)) {
      if (apc_exists($user_key)) {
        apc_inc($user_key);
      } else {
        apc_store($user_key, 1);
      }
    }
  }
}

function user_locked($user) {
  if (empty($user)) { return null; }

  $config = option('config');
  $user_key = 'fail_user_' . $user['id'];
  return apc_fetch($user_key) >= $config['user_lock_threshold'];
}

# FIXME
function ip_banned() {
  $config = option('config');
  $ip_key = 'fail_ip_' . $_SERVER['REMOTE_ADDR'];
  return apc_fetch($ip_key) >= $config['ip_ban_threshold'];
}

function attempt_login($login, $password) {

  $apc_key = "login_" . $login;
  $user = apc_fetch($apc_key);

  if (ip_banned()) {
    login_log(false, $login, isset($user['id']) ? $user['id'] : null);
    return ['error' => 'banned'];
  }

  if (user_locked($user)) {
    login_log(false, $login, $user['id']);
    return ['error' => 'locked'];
  }

  if (!empty($user) && calculate_password_hash($password, $user['salt']) == $user['password_hash']) {
    login_log(true, $login, $user['id']);
    return ['user' => $user];
  }
  elseif (!empty($user)) {
    login_log(false, $login, $user['id']);
    return ['error' => 'wrong_password'];
  }
  else {
    login_log(false, $login);
    return ['error' => 'wrong_login'];
  }
}

function current_user() {
  if (empty($_SESSION['user_id'])) {
    return null;
  }

  $apc_key = "user_" . $_SESSION['user_id'];

  if (!apc_exists($apc_key)) {
    unset($_SESSION['user_id']);
    return null;
  } else {
    $user = apc_fetch($apc_key);
  }

  return $user;
}

function last_login() {
  $user = current_user();
  if (empty($user)) {
    return null;
  }
  return apc_fetch("last_login_" . $user['id']);
}

function banned_ips() {

  $db = option('db_conn');
  $threshold = option('config')['ip_ban_threshold'];
  $ips = [];

  $stmt = $db->prepare('SELECT ip FROM (SELECT ip, MAX(succeeded) as max_succeeded, COUNT(1) as cnt FROM login_log GROUP BY ip) AS t0 WHERE t0.max_succeeded = 0 AND t0.cnt >= :threshold');
  $stmt->bindValue(':threshold', $threshold);
  $stmt->execute();
  $not_succeeded = $stmt->fetchAll(PDO::FETCH_COLUMN, 0);
  $ips = array_merge($not_succeeded);

  $stmt = $db->prepare('SELECT ip, MAX(id) AS last_login_id FROM login_log WHERE succeeded = 1 GROUP by ip');
  $stmt->execute();
  $last_succeeds = $stmt->fetchAll();

  foreach ($last_succeeds as $row) {
    $stmt = $db->prepare('SELECT COUNT(1) AS cnt FROM login_log WHERE ip = :ip AND :id < id');
    $stmt->bindValue(':ip', $row['ip']);
    $stmt->bindValue(':id', $row['last_login_id']);
    $stmt->execute();
    $count = $stmt->fetch(PDO::FETCH_ASSOC)['cnt'];
    if ($threshold <= $count) {
      array_push($ips, $row['ip']);
    }
  }
//  apc_clear_cache("user");
  return $ips;
}

function locked_users() {
  $threshold = option('config')['user_lock_threshold'];
  $user_ids = [];

  $db = option('db_conn');

  $stmt = $db->prepare('SELECT login FROM (SELECT user_id, login, MAX(succeeded) as max_succeeded, COUNT(1) as cnt FROM login_log GROUP BY user_id) AS t0 WHERE t0.user_id IS NOT NULL AND t0.max_succeeded = 0 AND t0.cnt >= :threshold');
  $stmt->bindValue(':threshold', $threshold);
  $stmt->execute();
  $not_succeeded = $stmt->fetchAll(PDO::FETCH_COLUMN, 0);
  $user_ids = array_merge($not_succeeded);

  $stmt = $db->prepare('SELECT user_id, login, MAX(id) AS last_login_id FROM login_log WHERE user_id IS NOT NULL AND succeeded = 1 GROUP BY user_id');
  $stmt->execute();
  $last_succeeds = $stmt->fetchAll();

  foreach ($last_succeeds as $row) {
    $stmt = $db->prepare('SELECT COUNT(1) AS cnt FROM login_log WHERE user_id = :user_id AND :id < id');
    $stmt->bindValue(':user_id', $row['user_id']);
    $stmt->bindValue(':id', $row['last_login_id']);
    $stmt->execute();
    $count = $stmt->fetch(PDO::FETCH_ASSOC)['cnt'];
    if ($threshold <= $count) {
      array_push($user_ids, $row['login']);
    }
  }

  return $user_ids;
}

dispatch_get('/', function() {
  return html('index.html.php');
});

dispatch_post('/login', function() {
  $result = attempt_login($_POST['login'], $_POST['password']);
  if (!empty($result['user'])) {
    session_regenerate_id(true);
    $_SESSION['user_id'] = $result['user']['id'];
    return redirect_to('/mypage');
  }
  else {
    switch($result['error']) {
      case 'locked':
        flash('notice', 'This account is locked.');
        break;
      case 'banned':
        flash('notice', "You're banned.");
        break;
      default:
        flash('notice', 'Wrong username or password');
        break;
    }
    //Dirty hack...
    return header('Location: /?' . $result['error']);
  }
});

dispatch_get('/mypage', function() {
  $user = current_user();

  if (empty($user)) {
    flash('notice', 'You must be logged in');
    //Dirty hack...
    return header('Location: /?nologin');
  }
  else {
    set('user', $user);
    set('last_login', last_login());
    return html('mypage.html.php');
  }
});

dispatch_get('/report', function() {
  return json_encode([
    'banned_ips' => banned_ips(),
    'locked_users' => locked_users()
  ]);
});

dispatch_get('/init', function() {
    apc_clear_cache("user");
    $db = option('db_conn');

    $stmt = $db->prepare('SELECT * FROM users');
    $stmt->execute();
    while ($user = $stmt->fetch(PDO::FETCH_ASSOC)) {
      apc_store("login_" . $user['login'], $user);
      apc_store("user_" . $user['id'], $user);
    }

    $stmt = $db->prepare('SELECT * FROM login_log');
    $stmt->execute();
    while ($log = $stmt->fetch(PDO::FETCH_ASSOC)) {
      login_log((bool)$log['succeeded'], $log['login'], $log['user_id'], $log['ip'], $log['created_at'], false);
    }
});

run();

my.cnf

[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
symbolic-links=0

max_allowed_packet=300M

skip-name-resolve
thread-cache-size = 10

sort-buffer-size                = 256K
read-buffer-size                = 256K
read-rnd-buffer-size            = 256K
join-buffer-size                = 256K

tmp-table-size                  = 64M
max-heap-table-size             = 64M

innodb-buffer-pool-size         = 1024M
innodb-log-file-size            = 16M
innodb-log-buffer-size          = 8M

#slow-query-log                  = 1
#slow-query-log-file             = /tmp/mysql_slow.log
#log_queries_not_using_indexes

#innodb_buffer_pool_dump_at_shutdown = 1
#innodb_buffer_pool_dump_now         = 1
#innodb_buffer_pool_load_at_startup  = 1
#innodb_buffer_pool_load_now         = 1

performance_schema = 0

[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

nginx.conf

worker_processes  4;

worker_rlimit_nofile  20000;
pcre_jit on;

events {
  worker_connections  4096;
  use epoll;
}

http {
  include /etc/nginx/mime.types;
  sendfile               on;
  tcp_nopush             on;
  tcp_nodelay            on;
  send_timeout           10;
  keepalive_timeout      5 3;
  keepalive_requests     30;
  output_buffers         1 64k;
  etag                   off;

  client_header_timeout        5;
  client_body_timeout          5;
  client_body_temp_path        /dev/shm/client_temp 1 2 3;
    client_max_body_size         10m;
  client_body_buffer_size      32k;
  client_header_buffer_size    2k;
  large_client_header_buffers  4 8k;

  server_tokens    off;
  access_log       off;
 
  upstream php-fpm {
    server unix:/dev/shm/php-fpm.sock;
  }

  server {
    location ~ ^/(images|stylesheets) {
      root /dev/shm/public;
      break;
    }

    location = / {
       root /dev/shm/public;
       if ($args ~ 'locked') {
         rewrite ^(.*)$ /index_locked.html break;
       }
       if ($args ~ 'banned') {
         rewrite ^(.*)$ /index_banned.html break;
       }
       if ($args ~ 'wrong') {
         rewrite ^(.*)$ /index_wrong.html break;
       }
       if ($args ~ 'nologin') {
         rewrite ^(.*)$ /index_nologin.html break;
       }
       rewrite ^(.*)$ /index.html break;
       break;
    }

    location / {
      root /home/isucon/webapp/php/src;

      fastcgi_pass php-fpm;
      fastcgi_index index.php;
      fastcgi_read_timeout 120;

      fastcgi_param  SCRIPT_FILENAME    $document_root$fastcgi_script_name;
      fastcgi_param  QUERY_STRING       $query_string;
      fastcgi_param  REQUEST_METHOD     $request_method;
      fastcgi_param  CONTENT_TYPE       $content_type;
      fastcgi_param  CONTENT_LENGTH     $content_length;

      fastcgi_param  SCRIPT_NAME        $fastcgi_script_name;
      fastcgi_param  REQUEST_URI        $request_uri;
      fastcgi_param  DOCUMENT_URI       $document_uri;
      fastcgi_param  DOCUMENT_ROOT      $document_root;
      fastcgi_param  SERVER_PROTOCOL    $server_protocol;
      fastcgi_param  HTTPS              $https if_not_empty;

      fastcgi_param  GATEWAY_INTERFACE  CGI/1.1;
      fastcgi_param  SERVER_SOFTWARE    nginx/$nginx_version;

      fastcgi_param  REMOTE_ADDR        $http_x_forwarded_for;
      fastcgi_param  REMOTE_PORT        $remote_port;
      fastcgi_param  SERVER_ADDR        $server_addr;
      fastcgi_param  SERVER_PORT        $server_port;
      fastcgi_param  SERVER_NAME        $server_name;

      fastcgi_param  REDIRECT_STATUS    200;

      rewrite ^(.*)$ /index.php?$1 break;
    }
  }
}

php-fpm.conf

[www]
;user = isucon
;group = isucon
listen = /dev/shm/php-fpm.sock
listen.owner = isucon
listen.group = isucon
listen.mode  = 0666
;listen = 0.0.0.0:8080

pm = static
pm.max_children = 4
pm.start_servers = 4
pm.min_spare_servers = 4
pm.max_spare_servers = 4
pm.process_idle_timeout = 0
pm.max_requests = 0
pm.status_path = /status
ping.path = /ping

php.ini

zend_extension=/home/isucon/.local/php/lib/php/extensions/no-debug-non-zts-20131226/opcache.so
opcache.memory_consumption=128
opcache.interned_strings_buffer=8
opcache.max_accelerated_files=4000
opcache.revalidate_freq=0
opcache.fast_shutdown=1
opcache.enable_cli=1
opcache.validate_timestamps=0
opcache.save_comments=0
opcache.load_comments=0

session.save_handler=files
session.save_path=/dev/shm/

extension=/home/isucon/.local/php/lib/php/extensions/no-debug-non-zts-20131226/apcu.so
apc.shm_size=1024M