unicorn stack trace

Mysql2::Error (Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)):
  vendor/bundle/ruby/1.9.1/gems/mysql2-0.3.11/lib/mysql2/client.rb:44:in `connect'
  vendor/bundle/ruby/1.9.1/gems/mysql2-0.3.11/lib/mysql2/client.rb:44:in `initialize'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/mysql2_adapter.rb:16:in `new'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/mysql2_adapter.rb:16:in `mysql2_connection'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_pool.rb:315:in `new_connection'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_pool.rb:325:in `checkout_new_connection'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_pool.rb:247:in `block (2 levels) in checkout'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_pool.rb:242:in `loop'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_pool.rb:242:in `block in checkout'
  /usr/local/rvm/rubies/ruby-1.9.3-head/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_pool.rb:239:in `checkout'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_pool.rb:102:in `block in connection'
  /usr/local/rvm/rubies/ruby-1.9.3-head/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_pool.rb:101:in `connection'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_pool.rb:410:in `retrieve_connection'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_specification.rb:171:in `retrieve_connection'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_specification.rb:145:in `connection'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/query_cache.rb:67:in `rescue in call'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/query_cache.rb:61:in `call'
  vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/connection_adapters/abstract/connection_pool.rb:479:in `call'
  vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.13/lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
  vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.13/lib/active_support/callbacks.rb:405:in `_run__932183096__call__962942844__callbacks'
  vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.13/lib/active_support/callbacks.rb:405:in `__run_callback'
  vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.13/lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
  vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.13/lib/active_support/callbacks.rb:81:in `run_callbacks'
  vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.13/lib/action_dispatch/middleware/callbacks.rb:27:in `call'
  vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.13/lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
  vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.13/lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
  vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.13/lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
  vendor/bundle/ruby/1.9.1/gems/railties-3.2.13/lib/rails/rack/logger.rb:32:in `call_app'
  vendor/bundle/ruby/1.9.1/gems/railties-3.2.13/lib/rails/rack/logger.rb:16:in `block in call'
  vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.13/lib/active_support/tagged_logging.rb:22:in `tagged'
  vendor/bundle/ruby/1.9.1/gems/railties-3.2.13/lib/rails/rack/logger.rb:16:in `call'
  vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.13/lib/action_dispatch/middleware/request_id.rb:22:in `call'
  vendor/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/methodoverride.rb:21:in `call'
  vendor/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/runtime.rb:17:in `call'
  vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.13/lib/active_support/cache/strategy/local_cache.rb:72:in `call'
  vendor/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/lock.rb:15:in `call'
  vendor/bundle/ruby/1.9.1/gems/rack-cache-1.2/lib/rack/cache/context.rb:136:in `forward'
  vendor/bundle/ruby/1.9.1/gems/rack-cache-1.2/lib/rack/cache/context.rb:245:in `fetch'
  vendor/bundle/ruby/1.9.1/gems/rack-cache-1.2/lib/rack/cache/context.rb:185:in `lookup'
  vendor/bundle/ruby/1.9.1/gems/rack-cache-1.2/lib/rack/cache/context.rb:66:in `call!'
  vendor/bundle/ruby/1.9.1/gems/rack-cache-1.2/lib/rack/cache/context.rb:51:in `call'
  vendor/bundle/ruby/1.9.1/gems/railties-3.2.13/lib/rails/engine.rb:479:in `call'
  vendor/bundle/ruby/1.9.1/gems/railties-3.2.13/lib/rails/application.rb:223:in `call'
  vendor/bundle/ruby/1.9.1/gems/railties-3.2.13/lib/rails/railtie/configurable.rb:30:in `method_missing'
  vendor/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn/http_server.rb:552:in `process_client'
  vendor/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn/http_server.rb:632:in `worker_loop'
  vendor/bundle/ruby/1.9.1/gems/newrelic_rpm-3.6.0.78/lib/new_relic/agent/instrumentation/unicorn_instrumentation.rb:22:in `call'
  vendor/bundle/ruby/1.9.1/gems/newrelic_rpm-3.6.0.78/lib/new_relic/agent/instrumentation/unicorn_instrumentation.rb:22:in `block (4 levels) in <top (required)>'
  vendor/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn/http_server.rb:500:in `spawn_missing_workers'
  vendor/bundle/ruby/1.9.1/gems/unicorn-4.6.2/lib/unicorn/http_server.rb:142:in `start'
  vendor/bundle/ruby/1.9.1/gems/unicorn-4.6.2/bin/unicorn_rails:209:in `<top (required)>'
  vendor/bundle/ruby/1.9.1/bin/unicorn_rails:23:in `load'
  vendor/bundle/ruby/1.9.1/bin/unicorn_rails:23:in `<main>'