Class: ActiveRecord::ConnectionAdapters::ConnectionPool

Inherits:
Object
  • Object
show all
Defined in:
lib/active_record/fiber_patches.rb

Overview

ActiveRecord’s connection pool is based on threads. Since we are working with EM and a single thread, multiple fiber design, we need to provide our own connection pool that keys off of Fiber.current so that different fibers running in the same thread don’t try to use the same connection.

Instance Method Summary collapse

Constructor Details

#initialize(spec) ⇒ ConnectionPool

Returns a new instance of ConnectionPool.



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# File 'lib/active_record/fiber_patches.rb', line 52

def initialize(spec)
  @spec = spec

  # The cache of reserved connections mapped to threads
  @reserved_connections = {}

  # The mutex used to synchronize pool access
  @connection_mutex = FiberedMonitor.new
  @queue = @connection_mutex.new_cond

  # default 5 second timeout unless on ruby 1.9
  @timeout = spec.config[:wait_timeout] || 5

  # default max pool size to 5
  @size = (spec.config[:pool] && spec.config[:pool].to_i) || 5

  @connections = []
  @checked_out = []
end

Instance Method Details

#clear_stale_cached_connections! ⇒ Object 



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# File 'lib/active_record/fiber_patches.rb', line 72

def clear_stale_cached_connections!
  cache = @reserved_connections
  keys = Set.new(cache.keys)

  ActiveRecord::ConnectionAdapters.fiber_pools.each do |pool|
    pool.busy_fibers.each_pair do |object_id, fiber|
      keys.delete(object_id)
    end
  end

  keys.each do |key|
    next unless cache.has_key?(key)
    checkin cache[key]
    cache.delete(key)
  end
end