ruby-on-rails - 我的应用程序一直在创建数据库连接，我该如何追踪原因？

Question

我有一个在 Heroku 上运行的 Ruby on Rails 应用程序。我不断在日志中收到这些消息:

2015-05-05T16:11:14Z app[postgres.27102]: [AQUA] connection received: host=xx.xxx.xx.26 port=60278
2015-05-05T16:11:14Z app[postgres.27102]: [AQUA] connection authorized: user=postgres database=somedb
2015-05-05T16:11:14Z app[postgres.27103]: [AQUA] connection received: host=xx.xxx.xx.26 port=60291
2015-05-05T16:11:14Z app[postgres.27103]: [AQUA] connection authorized: user=postgres database=postgres
2015-05-05T16:11:18Z app[postgres.27104]: [AQUA] connection received: host=xx.xxx.x.166 port=54180
2015-05-05T16:11:18Z app[postgres.27104]: [AQUA] connection authorized: user=postgres database=somedb
2015-05-05T16:11:23Z app[postgres.27105]: [AQUA] connection received: host=xx.xxx.x.166 port=55488
2015-05-05T16:11:23Z app[postgres.27105]: [AQUA] connection authorized: user=postgres database=somedb
2015-05-05T16:11:28Z app[postgres.27106]: [AQUA] connection received: host=xx.xxx.x.166 port=56774
2015-05-05T16:11:28Z app[postgres.27106]: [AQUA] connection authorized: user=postgres database=somedb
2015-05-05T16:11:28Z app[postgres.27107]: [AQUA] connection received: host=xx.xxx.x.166 port=56854
2015-05-05T16:11:28Z app[postgres.27107]: [AQUA] connection authorized: user=postgres database=somedb
2015-05-05T16:11:28Z app[postgres.27108]: [AQUA] connection received: host=xx.xxx.x.166 port=56885
2015-05-05T16:11:28Z app[postgres.27108]: [AQUA] connection authorized: user=postgres database=somedb
2015-05-05T16:11:28Z app[postgres.27109]: [AQUA] connection received: host=xx.xxx.x.166 port=56912
2015-05-05T16:11:28Z app[postgres.27109]: [AQUA] connection authorized: user=postgres database=somedb
2015-05-05T16:11:33Z app[postgres.27110]: [AQUA] connection received: host=xx.xxx.x.166 port=58039
2015-05-05T16:11:33Z app[postgres.27110]: [AQUA] connection authorized: user=postgres database=somedb
2015-05-05T16:11:38Z app[postgres.27111]: [AQUA] connection received: host=xx.xxx.x.166 port=59387
2015-05-05T16:11:38Z app[postgres.27111]: [AQUA] connection authorized: user=postgres database=somedb
2015-05-05T16:11:43Z app[postgres.27112]: [AQUA] connection received: host=xx.xxx.x.166 port=60944
2015-05-05T16:11:43Z app[postgres.27112]: [AQUA] connection authorized: user=postgres database=somedb
2015-05-05T16:11:14+00:00 app[heroku-postgres]: source=HEROKU_POSTGRESQL_AQUA sample#current_transaction=511990 sample#db_size=203303096bytes sample#tables=17 sample#active-connections=2 sample#waiting-connections=0 sample#index-cache-hit-rate=0.99997 sample#table-cache-hit-rate=0.94699 sample#load-avg-1m=0.14 sample#load-avg-5m=0.25 sample#load-avg-15m=0.24 sample#read-iops=0.1875 sample#write-iops=1 sample#memory-total=7629448kB sample#memory-free=428388kB sample#memory-cached=6784860kB sample#memory-postgres=171732kB

我不知道是什么原因造成的。该应用程序运行 Cedar 10 堆栈、ruby 2.1.4、rails 3.2.11 和 puma 2.11.2，有 3 个工作线程和 1 个线程。它不会发生在开发或暂存环境中，只会发生在 Heroku 上。

运行:select application_name from pg_stat_activity; 显示:

        application_name         
---------------------------------

 puma: cluster worker 2: 3 [app]
 puma: cluster worker 1: 3 [app]
 puma: cluster worker 0: 3 [app]
 psql johnny interactive

这是我的 puma 配置文件(最小和最大线程数等于 1):

workers Integer(ENV['PUMA_WORKERS'] || 3)
threads Integer(ENV['MIN_THREADS']  || 1), Integer(ENV['MAX_THREADS'] || 16)

preload_app!

rackup      DefaultRackup
port        ENV['PORT']     || 3000
environment ENV['RACK_ENV'] || 'development'

on_worker_boot do
  # worker specific setup
  ActiveSupport.on_load(:active_record) do
    config = ActiveRecord::Base.configurations[Rails.env] ||
                Rails.application.config.database_configuration[Rails.env]
    config['pool'] = ENV['MAX_THREADS'] || 16
    ActiveRecord::Base.establish_connection(config)
  end
end

关于如何追踪这个的任何想法？

更新:我在 on_worker_boot block 中添加了一条调试消息，它只在应用程序启动时被调用，所以我仍然不知道为什么要建立连接经常。

Answer 1

这是关于建立与 Postgres 连接的临时日志。因此，只需忽略它们或尝试在 postgresql.conf 中禁用它们(请参阅 log_connections 选项)，但我认为您无法在 Heroku 中访问它。