Question

您好我们正在与Unicorn和Sidekiq一起使用Heroku的Cedar堆栈。我们间歇性地得到以下错误

BurnThis ActiveRecord::StatementInvalid: PG::UnableToSend: SSL SYSCALL error: EOF detected

ActiveRecord::StatementInvalid: PG::ConnectionBad: PQconsumeInput() SSL SYSCALL error: Connection timed out

有没有人知道这些错误的直接原因是什么？与我们的数据库连接太多了吗？我们已经通过以下方式设置了分叉：

unicorn.rb

worker_processes Integer(ENV["WEB_CONCURRENCY"] || 3)
timeout 30
preload_app true

before_fork do |server, worker|
  Signal.trap 'TERM' do
    puts 'Unicorn master intercepting TERM and sending myself QUIT instead'
    Process.kill 'QUIT', Process.pid
  end

  defined?(ActiveRecord::Base) and
    ActiveRecord::

Base.connection.disconnect!
end

after_fork do |server, worker|
  Signal.trap 'TERM' do
    puts 'Unicorn worker intercepting TERM and doing nothing. Wait for master to send QUIT'
  end

  # other setup
  if defined?(ActiveRecord::Base)
    config = Rails.application.config.database_configuration[Rails.env]
    config['adapter'] = 'postgis'
    config['pool']              = ENV['DB_POOL'] || 5
    config['reaping_frequency'] = ENV['DB_REAP_FREQ'] || 10 # seconds
    ActiveRecord::Base.establish_connection(config)
  end
end

和sidekiq.rb

Sidekiq.configure_server do |config|
  config.redis = { :url => ENV['REDIS_URL'], :namespace => 'btsidekiq' }

  if defined?(ActiveRecord::Base)
    config = Rails.application.config.database_configuration[Rails.env]
    config['adapter'] = 'postgis'
    config['pool']              = ENV['DB_POOL'] || 5
    config['reaping_frequency'] = ENV['DB_REAP_FREQ'] || 10 # seconds
    ActiveRecord::Base.establish_connection(config)
  end
end

Sidekiq.configure_client do |config|
  config.redis = { :url => ENV['REDIS_URL'], :namespace => 'btsidekiq' }
end

我们的数据库池大小相当大DB_POOL = 100，我们在PG数据库上显然同时支持500个连接。

Answer 1

此错误是由您的postgis适配器尝试使用ActiveRecord连接池中的陈旧/无效连接引起的。有两种方法可以解决这个问题：

调整连接池的大小以匹配线程数/进程
降低连接收割频率（Reaper检查池是否有死连接，每N秒）

要实现＃1，您需要设置适合Unicorn和Sidekiq的池大小，这可能有不同的需求。

Unicorn是单线程的，因此每个进程的默认池大小5连接对您来说是正确的。这将为每个WEB_CONCURRENCY后端独角兽工作者分配最多5个连接。您应该重置默认池大小并使用现有的unicorn.rb：

$> heroku config:set DB_POOL=5

config/initializers/sidekiq.rb

Sidekiq.configure_server do |config|
  pool_size = Sidekiq.options[:concurrency] + 2

  config.redis = { :url => ENV['REDIS_URL'], :namespace => 'btsidekiq', :size => pool_size }

  if defined?(ActiveRecord::Base)
    config = Rails.application.config.database_configuration[Rails.env]
    config['adapter'] = 'postgis'
    config['pool']              = pool_size
    config['reaping_frequency'] = ENV['DB_REAP_FREQ'] || 10 # seconds
    ActiveRecord::Base.establish_connection(config)
  end
end

我最好的猜测是，使用这么大的100连接池，你更有可能产生死连接。适当调整池的大小应该解决这个问题。

如果这不起作用，您应该尝试将DB_REAP_FREQ减少到5秒。

Heroku + Sidekiq：ActiveRecord :: StatementInvalid：PG :: UnableToSend：SSL SYSCALL错误：检测到EOF

1 个答案: