Add ActiveRecord::Base.connection_pool.stat

[Paxa]

Example:

p ActiveRecord::Base.connection_pool.stat
{
  max: 25,
  total: 1,
  busy: 1,
  dead: 0,
  idle: 0,
  num_waiting: 0,
  checkout_timeout: 5
}

Related to #26898

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[Paxa]

@matthewd is it how you think or it?

[matthewd]

👍

Wrap the method body in a synchronize do block to ensure the numbers are consistent.

[Paxa]

Done

[jrafanie]

Great idea! Personal preference but max and total are a bit confusing to me. Naming is hard. We instantiate a pool with a "size". A pool contains "connections". Therefore, my poor naming would be:

size: size
connections: @connections.size

Either way, this is helpful!

[rafaelfranca]

Yeah. I like the naming suggested by @jrafanie

[Paxa]

Changed to

{ size: 15, connections: 1, busy: 1, dead: 0, idle: 0, waiting: 0, checkout_timeout: 5 }

Also waiting: feels odd to me, because all other values related to connections, but waiting are consumers. Will it be better to name it as waiting_in_queue or queue?

[rafaelfranca]

# Example:
#
#    ActiveRecord::Base.connection_pool.stat # => { size: 15, connections: 1, busy: 1, dead: 0, idle: 0, waiting: 0, checkout_timeout: 5 }

[rafaelfranca]

Could you add a CHANGELOG entry and squash your commits?

[Paxa]

Done