How to increase the default timeout of GenServer elixir?

The default is probably 5 secs. Can someone please tell me how to increase this?

You just need to add a timeout…

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I knw that but what is the syntax to enhance that?

I am using like this:
def init(initial_data) do
{:ok, initial_data, timeout(5000000)}

It gives me this error:
undefined function timeout/1

{:ok, initial_data, 5_000_000}

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That timeout is used to detect a lull between messages:

Also I suspect that the timeout has to be renewed on each handle_* return value - so it doesn’t act as a “default”.

This is entirely unrelated to the timeout parameter on


Just to confirm You need to renew on each call, and You receive a timeout message after delay that You can use to close the server.

  @impl GenServer
  def handle_info(:timeout, state), do: {:stop, {:shutdown, :timeout}, state}

If done wrong, You could see your workers shuting down automatically :slight_smile:

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As you always should expose a wrapper around and never see calls to it somewhere else, that wrapper needs to specify the timeout:

def foo(arg), do: GenServer.calll(__MODULE__, {:foo, arg}, 10_000)

This will use a timeout of 10 seconds.


Beware this would not work if you need several instances of __MODULE__.

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Consider following's example and give the client a way to change the timeout if necessary.

def foo(server, arg, timeout \\ 10_000), 
  do:, {:foo, arg}, timeout)

Now foo/3's default timeout is 10 seconds.